Grand Slam Cup · SF · Hard · 14 Dec 1991

Michael Stich v David Wheaton

138–149 in points · David Wheaton won

Why it went the way it did

David Wheaton won 3.8 more points than Michael Stich relative to what the serve alone predicted. Michael Stich's biggest leaks: return execution −10.5, slice execution −2.1, net direction choices −1.9.

Each shot moves its hitter's chance of winning the point. Those moves are split into direction choice, shot selection and execution, and summed here. Read both columns together: one player's gain is the other's loss.

Shot	Michael Stich				David Wheaton
Shot	Dir	Sel	Exec	Total	Dir	Sel	Exec	Total
Serve 1st	+0.6	+2.0	+3.5	+6.1	−1.5	+2.7	−1.9	−0.6
Serve 2nd	−0.2	+2.4	−1.2	+0.9	−0.2	+1.3	−2.9	−1.7
Return	−0.8	+0.6	−10.5	−10.7	+0.2	+0.7	+2.7	+3.5
Forehand	−0.4	+0.4	+1.7	+1.6	+0.2	+1.8	−1.8	+0.2
Backhand	−0.3	+0.2	−1.4	−1.6	−0.2	+0.4	−2.4	−2.2
Slice	±0.0	−1.4	−2.1	−3.4	±0.0	−1.2	−0.5	−1.7
Net	−1.9	−0.5	+2.1	−0.2	+0.1	−0.2	−1.1	−1.2
Touch	+0.3	−0.5	−0.8	−1.0	−0.1	−2.0	+1.4	−0.7
All shots	−2.7	+3.1	−8.7	−8.3	−1.4	+3.6	−6.6	−4.4

Set by set

Set	Michael Stich	David Wheaton	Net, Michael
1	−2.3	−3.3	+1.0
2	−0.6	−0.4	−0.2
3	−5.3	−0.7	−4.6

Adaptation

First-serve direction mix set by set, with the share of points each direction won. The scores measure whether the server moved toward the directions that had been winning earlier in this match, set to set and every two to three service games, in points per 100 first serves. Read them as a habit, not a gain: across the tour, a direction's edge in early sets barely predicts the later ones. Whether the returner responded can't be told apart from noise within one match.

Michael Stich serving

Set	Wide	Body	T
1	45% 67%	3% 100%	53% 81%
2	42% 52%	2% 0%	56% 61%
3	48% 63%	3% 0%	50% 75%

Set to set −0.18 per 100 first serves in sets 2+

Within sets +0.70 per 100 first serves, every two to three service games

David Wheaton serving

Set	Wide	Body	T
1	31% 81%	35% 67%	33% 65%
2	44% 50%	17% 67%	39% 57%
3	36% 71%	28% 82%	36% 86%

Set to set +0.53 per 100 first serves in sets 2+

Within sets +0.46 per 100 first serves, every two to three service games

Counterfactual: the best direction every time

If each shot had gone in the direction that is usually worth most for that stroke and position, this is how many more points each player would expect to win. It's an upper bound: the best direction isn't always on, and the chart can't see the ball's pace or position.

Michael Stich

19.7 points left on the table across 326 shots 6.03 per 100 shots

Serve +1: mid-depth return to your middle, you at net hit BH volley through the middle ×7; BH volley crosscourt rates higher · 1.76 pts
Serve +1: mid-depth return to your backhand side, you at net hit BH volley through the middle ×4; BH volley crosscourt rates higher · 1.12 pts
Rally, shots 5–8: drive to your backhand side, you at net hit BH volley through the middle ×4; BH volley crosscourt rates higher · 1.04 pts
Return of a 2nd serve, body, deuce court, server rushing the net hit BH through the middle ×5; BH crosscourt rates higher · 0.79 pts

David Wheaton

12.1 points left on the table across 292 shots 4.13 per 100 shots

Serve +1: short return to your middle, you at net hit BH volley through the middle ×4; BH volley crosscourt rates higher · 0.80 pts
Return of a 2nd serve, body, deuce court, server rushing the net hit BH through the middle ×4; BH crosscourt rates higher · 0.63 pts
Return of a 1st serve, wide, deuce court, server rushing the net hit FH through the middle ×7; FH crosscourt rates higher · 0.53 pts
Serve +1: mid-depth return to your middle, you at net hit BH volley through the middle ×2; BH volley crosscourt rates higher · 0.50 pts