Your Strokes:
Francis Tiafoe Serve

Analyzed by John Yandell

I have filmed American junior Francis Tiafoe several times at the Easter Bowl over the years. Francis won the tournament (for American juniors) in the 18s this spring, following his win at the Orange Bowl in December over the cream of the international field. All that at the current age of 16.

No one can predict future success in tennis, but I can say that after watching hundreds of juniors over the years, Francis appears to have incredible, natural explosiveness in his strokes, combined with great fluidity and an instinctive feel for the court.

When you look at his serve you see the explosiveness. You also see high level technical elements. But you also see components that vary substantially from elite serving motions.

It's not unheard of for players, even for players who go on to become Grand Slam winners, to make technical changes at various stages of their careers. Especially if they have problems that are clearly affecting the outcome of matches.

With Francis his serve has been a weapon. The question is whether that can continue to happen.

So let's analyze the elements in his motion and compare them to high level pro technique. It goes without saying though that this is just my view and any decisions about change should be made by Francis and his coaches.

Racket Path

As we have seen in multiple articles on Tennisplayer, the first key to look for in high level serving is the racket path in the upward swing. Francis has a deep racket drop.

If you look at the angle of his upper arm you can see Francis has great shoulder flexibility. At the drop his upper arm is close to horizontal or in line with his torso.

This indicates that there is great backward or external rotation of the shoulder. The ability to rotate the arm backwards from the shoulder joint is the hallmark of great servers such as Pete Sampras and Andy Roddick. More external rotation means more forward or internal rotation in the upward motion, and this is huge contributor to racket speed.

You can see how explosive Francis is if you look at that forward rotation in the upward swing. Watch how fast his arm rotates, turning over roughly 180 degrees very early in the followthrough.

Arm Motion

The hand and arm rotation in the upward swing may be pro level, but when you look at the movement of his arms as he winds up, it's very unusual. Both the racket motion with the right arm and the tossing motion with the left are different.

Francis has a substantial lag in the timing of his windup something which is not uncommon for of elite servers, as Doug Eng's Tennisplayer articles have shown. (Click Here.) But Francis version of the lag is different.

He first drops the arm and racket downward. But look what happens next. As he raises the arm upward, it moves dramatically to his right side. At one point his arm is actually pointing directly at the sideline.

So does Francis know something we don't? Will other players be copying this wind up one day? I don't think so.

The questions to ask are: How is this motion affecting his racket drop? And would he have a better racket drop with a different windup?

You could also call his wind up abbreviated, but it's very different from Andy Roddick's motion in which the arm and racket go up almost immediately and move far less to the side. (Click Here for my analysis of Andy's motion.)

If you look closely at his racket face at the drop it's not as far to the right or in line with the torso edge at the same right angle as you see with the game's elite servers. There is a slight angling across the back which affects the path of the upward swing.

But now let's analyze the other arm, the tossing arm. That motion is even more unusual than the windup. The tossing arm never moves down, it just goes directly upward. Some players do that. But when Francis tosses, the elbow also bends dramatically.

It bends so much that his forearm is literally at a right angle to his upper arm, over his head, and essentially parallel to the court. That's radically different than any other elite server I have ever filmed.

A core commonality in great serving is the extension of the tossing arm at the completion of the tossing motion. It's pointing upward, angled toward the sky.

That makes the tossing motion simpler and more of a release than a throw. But there is a reason for that beyond controlling the toss.

That angle helps the server use his shoulders. There is a relationship between the extension of the arm and the tilt of the shoulders, that is, the angle between the front and rear shoulder at the completion of the tossing motion.

Look at the shoulder tilt in Federer's motion, something you see in all great servers. The angle across the shoulders is something like 30 to 45 degrees.

This position sets up what the Australian biomechanist Bruce Elliot calls "the cartwheel." This is shoulder over shoulder rotation in the upward swing. (Click Here.)

It's a key power source. But Francis doesn't have it. If you look at the line of his shoulders when the tilt should be maximized, there is virtually none. A line across the shoulders is essentially parallel to the court.

Stance

Francis is using a version of a sliding or pinpoint stance, also sometimes called the step up. This means as the motion starts he brings his rear, right foot up and directly behind the front foot. There is nothing necessarily wrong with the pinpoint stance as a high percentage of top players both men and especially women use it.

What is interesting for Francis however is the level of the knee bend. When he brings the rear foot up he creates some bend in both legs. But again it's not at the level of the top servers, even some of the top pinpoint servers. Could it be more? Undoubtedly yes.

Body Rotation

The other area where Francis's motion differs the most from most elite servers is in the body rotation. It's less than all the top men, and even many of the top women. It's also less than the majority of elite juniors.

In his starting stance his shoulders are open to the net, not just slightly but something like 30 to 45 degrees. Then when he takes his arm to right in that unusual windup he actually opens his shoulders even more. The angle at that point could be approaching 60 degrees. His shoulders are moving in the opposite direction from virtually all elite servers.

Eventually the shoulders change direction turning back clockwise. But they return only to about perpendicular to the net. This is the place where many or most players start.

So there is virtually no body coiling from the shoulders. Compare this to Federer who turns off the ball something close to 45 degrees.

How is that turn valuable? When the shoulders turn away in the wind up, they rotate further going back into the shot. This contributes to racket head speed and also to disguise.

Francis is training at one the top junior centers in the country. Certainly his coaches are studying his technique and are aware of some or all of these issues. But analysis is different than change.

Like I said, watching Francis in person you see how explosive his swings really are. I would love to see a different windup, whether conventional or abbreviated. No doubt he also needs to alter the motion of the tossing arm to create a better shoulder angle.

I would also love to see what happened if he experimented with a better starting position with the shoulders square. And with deeper knee bend, more body turn-- possibly using the platform stance to facilitate those experiments.

In any case I have really enjoyed watching Francis play because of his shot making, his court sense, and fight. He shows a tremendous amount for a junior and especially for a guy who is 16. I suspect the next time I film him his serve is going to look substantially different--and probably be even more effective.