Felix Auger Aliassime

Pendulums and hinges—swingweight—in-to-out—consistency

Felix Auger Aliassime bowed out in the second round of the US Open to Jack Draper last week, in a performance riddled with errors from both wings. It was not unlike his match at the Canadian Open against Casper Ruud, and overall his form and results have varied wildly over the year. Following the match against Ruud, Auger Aliassime had this to say:

“This is not usual for me, after playing two good matches, to lose the way I did today, especially at a tournament like this one.”

I replayed the match against Draper and made a crude count of the misses off both forehands and backhands for each player.

These numbers do not include drop shot attempts or easy short ball winners. Second serve returns where the player looked set were counted. As usual, I am interested in seeing how well stock topspin shots from the baseline were holding up.

Felix’s numbers reflect just how erratic he was in this match. As the commentator mentioned early in the first set:

“Their (Felix and Denis Shapovalov) upside when they’re playing well—their talent level—is as good as anybody. They both can’t sustain it. They’ll give you games with just errors, and right now, Felix is just filled with errors. We’ve played only two games and he’s made eight unforced errors.”

“It almost feels as though the last few matches I’ve seen from Felix he doesn't have shot tolerance. It’s four balls. If you can get four balls in that’s good enough.”

Draper was solid off both sides despite playing a tactically pretty poor match and directing a lot of traffic to the Auger Aliassime forehand—especially in the second and third sets. It didn’t really matter in the end, because Auger Aliassime was spraying balls off both wings in a similar fashion to his Canadian Open loss. A look at his US hardcourt swing showcases the up-and-down nature of his form these past weeks:

Two top-10 wins with three straight-set losses.

The question is why? Why does this guy push Medvedev to five sets in the semi-finals of the Australian Open, push Rafa to five sets at the French Open, but lose to Ruud 6/1 6/2 and Draper in straight on a hard court? NYC. Night session. Top-10 in the world. To be brutally honest he played very subpar tennis when at this stage of his career he should have taken down Draper on the biggest stage. He’s obviously a huge talent and has been earmarked as a future great for years. Once again, I’m going to make the case for technical efficiency as a major part of the problem.

Felix’s forehand

You don’t even have to play the video above to capture what I’m suggesting. Just look at the racquet face angles in both set-ups (Alcaraz on the right for comparison) on the thumbnail. Despite both players using similar semi-western grips, Felix’s strings are pointing down to his shoes, whereas Alcaraz has his strings facing the back fence.¹ Alcaraz’s set-up is in line with Federer², Djokovic, Wawrinka, Thiem, Nalbandian, Davydenko, and a host of others.³ Felix's strings face more forwards because he flexes his wrist—something I have written about in-depth before in Death of a Forehand—as has become vogue lately. We have seen numerous players emerge with this flexed wrist (Khachanov, Sock, Zverev, Tiafoe, Hurkacz, Musetti), especially in players with more extreme grips⁴, yet I contend that this is an inferior forehand that makes controlling the ball more difficult.⁵ An excerpt from Death of a Forehand- Part I:

“The extra degree of freedom a flexed wrist and/or a side-pointing racquet head places on the swing means that spin and power come at the expense of control. As Duane Knudson states in Biomechanical Principles of Tennis Technique, “Decreasing the number of body segments and the extent of their motion will increase the accuracy of the movement.” Shorter swings with fewer moving parts make for better timing.”

The Tennis Warehouse learning centre has done numerous tests related to tennis in conjunction with physicist Rodd Cross of the University of Sydney. One of these tests looks at the ‘double pendulum’ action of serves and forehands:

“Swinging a racquet is a process that is not easy to describe in words since the actions of all the various body segments are quite complicated. However, if we focus just on the forearm and the racquet then the task is a little easier, especially since these two segments by themselves act like a double pendulum. A double pendulum is just two single pendulums joined end to end.”

The wrist hinge

What is interesting here is that the wrist is also mentioned further along in the same Tennis Warehouse study:

“In tennis, the wrist is not just a passive hinge, like it is in a mechanical double pendulum, but plays an active role in controlling the racquet…In general, the player rotates the forearm at a controlled speed, using muscles in the upper arm, and uses the wrist as an extra aid to control exactly where the racquet needs to go.”

The wrist is an aid for control. If we want more control, we want fewer moving parts. Another excerpt from Death of a Forehand - Part I:

“For a more recent example, the video below highlights the textbook modern forehand. Notice how stable Davydenko’s wrist is from the beginning of the swing right up until contact; the range of movement is confined (extended to hyperextended). Speed is generated by getting the racquet head above his shoulders, with the racquet tip pointing to high noon, and using his body’s kinetic chain to uncoil. Reducing movement at the most distal joint allowed Davydenko to play from a hyper-aggressive court position and control a flat ball. Despite his small stature, he could pressure the very best players by holding the baseline, abbreviating the swing, and taking the ball early.”

It’s always difficult and somewhat risky making a technical change—especially when you’ve already had as much success as Felix has had. Motor patterns are sticky and natural tendencies are comfortable, but the point remains that I believe there is a better way and if a player was motivated to make an adjustment it is entirely possible. If I was coaching Felix, I’d be looking for ways to increase control in his forehand. How? To get the racquet head quieter.

1. Maintaining wrist extension in the set-up (getting strings more to the back fence, like Davydenko) to reduce the range of movement of the wrist just before acceleration. This would also naturally get his strings down—something I think helps with control.

2. Shortening the swing. Thiem did this and became a hardcourt threat. It allowed him to control a flat ball and play up in the court with more consistency.

3. Increasing racquet swingweight.⁶

The third point is one that I think can nudge a player toward a simpler, quieter swing. Miha Flisek, an engineer, racquet technician, and founder of impactingtennis.com, has written numerous in-depth (admittedly, most of it goes over my head) pieces on racquet properties. Some generalizations he came to from his research that I thought were interesting:

1. “High swingweight smoothes out the strokes and it makes it almost impossible to just arm the ball with bad technique. That is because the racket has a higher moment of inertia and you have to generate more momentum with your hand to get it moving and small deviations of your hand movement and muscle action don’t affect the racket head position and path so much.” You can see in players like Wawrinka (SW 360) and Djokovic (SW 370) the quiet wrist and huge torso rotation they use in their shots. Such swing styles may be implicitly learned/nudged because they used a heavy stick during development. I have no data on their racquet history growing up but it’s something that would be of interest to learn.

2. “More control and consistency also comes from the fact that with a higher swingweight you can swing at lower swing speeds to get the same amount of power and spin.”

Looking at Felix’s forehand compared to someone like Djokovic from the back perspective, we can see the full face of Djokovic’s racquet in the backswing—he has ‘closed’ the face to the back fence. Of course, this is due to differences in grip as well (Djokovic may be a little more extreme), but what is important is that Djokovic keeps his wrist quieter—he extends the wrist in his setup so there is little to be undone as he unwinds. Felix’s strings face the side fence because his wrist position trends toward flexion. As the racquet drops and he starts to unload, his wrist is going to transition from flexion —> neutral —> extension and then contact in hyperextension. Djokovic only goes from extension to hyperextension. Felix has more of a correction to make leading to contact. While Felix might generate more speed in this manner by loading energy in the wrist to create lag, it’s simply harder to replicate as there is more movement in the parts.

The more parts you load, the more parts you must unload.

Felix’s backhand

While Felix’s forehand can be a major weapon (and there is an argument there is nothing wrong with it technically) his backhand is a liability, and his recent backhand performances have shown a pretty glaring weakness. Again, his racquet head seems very noisy—there’s a lot of drop and wrist action. To be clear, I am an advocate for dropping the racquet head below the ball, but I think the major weakness in his backhand is due to the position his racquet head takes in the set-up. It’s outside his hands and away from his body, which makes the racquet head noisy and almost swinging out-to-in. For the detectives out there, pause their backhands on contact and notice how much more space Djokovic creates; his left elbow is far away from his body, whereas Felix’s is tucked right next to his stomach.

Swinging in-to-out

In tennis, we want to ideally have a natural draw (i.e., topspin) on our groundstrokes. Coaches might emphasize this by telling students to feel like they are getting the "outside" of the ball. To do that, we need to start inside the ball on the backhand. I’ve written previously about how I think Alcaraz’s backhand can get messy here. Below you can see the difference in set-up between Nalbandian and Alcaraz.

David Nalbandian v Carlos Alcaraz. Note how Nalbandian’s left arm works back close to his body and the racquet tip is facing the back fence/working inside the ball. Alcaraz’s tip is pointing more to the side, and his left elbow is away from his body. Nalbandian, Djokovic, Nadal, Nishikori, Safin, Medvedev, Sinner, Zverev, all exhibit a full turn of the racquet that gets the tip facing the back fence before accelerating so they swing from IN-to-OUT. Huge difference in swingweights as well (377 for Nalbandian, 316 for Alcaraz *based off what I could find on the internet*, so make of that what you will)

For an extreme example to understand the different swings each set-up produces, the video below does a great demonstration of why having the racquet head outside the hands in an abbreviated take-back is subpar for the backhand.⁷ Again, by just observing the thumbnail you can see the major difference in set-up position.

Felix has more in common with Steve Johnson’s backhand, unfortunately (Johnson almost exclusively slices in matches, such is the fragility in his topspin backhand). I feel that if Felix wants to improve his backhand he must make a technical change; no amount of talent or athleticism can run against efficient biomechanics, especially when you are competing against equally talented and athletic peers who are swinging more efficiently (Djokovic, Sinner, Medvedev, Zverev, Rafa, etc.). He needs to get the racquet tip further back/have a bigger unit turn so that he swings more in-to-out. Virtually every great backhand on tour has this characteristic⁸, and so far Felix isn't bucking the trend. I really think this is a fixable issue with a few solid weeks dedicated to getting the head inside the ball line.

Consistency

While Felix has been a promising talent for many years now, the reality of his game is that—apart from his serve—he is technically susceptible on his groundstrokes. Can he win a slam with his current game? Probably. He’s already been close now. But I don’t think his technique, as it currently stands, is good enough to dominate the game. Davydenko echoed similar sentiments when addressing the younger crop of players recently that I wrote about in-depth here:

“In my opinion, tennis is not making much progress. The players who are at the top now – not Nadal and Djokovic, but the younger generation –are not that good technically. I got surprised by that. It’s more physical – big serves, hitting hard–, but we still see that Nadal and Djokovic can control all this power over the new generation. They are still winning Slams and beating guys who are ten years younger than them, which is amazing. Anyway, I do not feel that the new generation is playing on an unbelievable level.”

The hot-and-cold nature of Felix’s results is (partly) a reflection of his swings. Some days it is going to work, but to win tournaments and rise to number 1 you need to raise the level of your worst tennis more than anything, as Nadal mentioned recently:

“The most important key in tennis that I think Federer, Djokovic and myself have is winning a lot of matches despite playing badly.”

When Felix plays badly, he simply misses too many balls to give himself a chance. To make a cross-sport comparison, Tiger said the same thing when addressing swing changes he made before his remarkable 2000 PGA season (video here):

“I felt like I couldn’t be in contention every time I teed it up with the swing I used to have. I felt that I was not hitting it in the right direction for the long haul…I think the main thing in those changes I’ve made is I’ve become more of a consistent player. My bad shots aren’t that bad, and my good shots are always going to be pretty good, but it’s the bad ones that are the key to shooting good solid numbers.”

A key feature of all-time greats is their incessant drive to improve, even when dominating the sport (Tiger was already dominating when he made the swing changes mentioned above). Djokovic’s serve evolved, Federer changed racquets, Nadal comes in more, and Thiem shortened his swings. For talented younger players like Felix who are still climbing the ladder to number 1, the reality of their swings needs to be addressed if they want to play well consistently.

1. Partly also due to different elbow positions, but the point remains that the wrist position is fundamentally different. Also, Nadal is somewhat like Felix now, but I contend he hit his forehand better when he had more wrist extension (like ~2010 or ~2013). Plus he uses a straight arm forehand which I would think reduces moving parts.

2. Due to grip differences (Federer = eastern forehand grip, Alcaraz = semi-western) the strings will face at different angles despite the same body and wrist positions.

3. Similar in their use of an upright racquet head and extended/neutral wrist position.

4. I will say that a flexed wrist is more common in extreme grips because their contact is probably closer to neutral/has more flexion/less extension. Berrettini, for example, has some flexion in his set-up, (looks to be a grip between semi-western and western) but he lays the racquet back/gets it into a position with the buttcap facing the ball or close to it with a short swing. It’s a short and simple swing and the racquet head looks much quieter to me compared to someone like Felix.

5. Less so for more extreme grips, as they make contact with less extension.

6. Felix’s racquet swingweight isn’t exactly light (345), but it’s not in the same ballpark as some of the other heavier players (Murray, Schwartzman, Cerundolo, Djokovic, Wawrinka, Nadal, Cilic, Berdych, etc.)

7. There are certain grips and swings where it can work. As the grip gets more conservative (like Kyrgios or Norrie) you can swing with the hands outside with a short flat bunt.

8. Medvedev, Zverev, Sinner, Nishikori, Nadal, Djokovic,