USTA League (and an increasing number of tournaments) are competed in a format that uses a super-breaker in lieu of a full 3rd set. One question raised during the recent Intercollegiate Tennis Association (ITA) World Tennis Number (WTN) coaches webinar was how the algorithm accounts for those super-breaker sets. As it turns out, the current WTN algorithm awards equal weight to super-breakers and full sets. It was one of the more interesting parts of the information shared.
The ITF has repeatedly made the claim that the experimental sets-only version of the WTN algorithm is as “accurate” as the one that was evaluated at the game-level granularity. I suspect that what the statement really means is that the two algorithms produce ratings that are similar, while avoiding the conundrum of how to process super-breakers in the game based version. In other words, “close enough.”
Theoretically, if a match goes to a super-breaker, the recent results during the previous two sets should point toward an expected win probability in the neighborhood of 50%. However, I know from direct experience that some players have exceptionally good records in tie-breakers while others struggle. I believe that the super-breaker is a crucible for high-fidelity match performance data.
I do not put a lot of stock into the data scraping site TennisRecord.com. In fact, the Fiend at Court household has a running moratorium on discussions based on the estimated ratings from that site. However, this is one of those situations where that data is “close enough” to illustrate my point. (Also, this gives me the chance to see the Trophy Husband spit out his coffee in self-righteous indignation after reading this paragraph over breakfast.)
I am very good in the super-breaker in lieu of 3rd set format and I have real data to back up that assertion. According to the detailed stats from TennisRecord.com, I have played 25 singles matches since 2014 that were decided by a super-breaker. I won 84% of those matches. To put that in context, during the same time period I have only won 45.8% of set tie-breakers and only 69% of my matches overall.
Essentially, I feel that if I can get a match to a super-breaker, I will win. Confidence is a powerful thing to carry into what should ostensibly be a coin-toss situation. The Umpire that I gave birth to calls that “insane confidence.” However, it is only crazy if you can’t back it up.
Additionally, the effect carries over into my doubles matches. Theoretically, I might have a less confident partner that certainly has to play the ball from time to time. I am 52-14 in doubles super-breakers for a 78.8% winning percentage. That is still in outlier territory.
Paradoxically, I fundamentally hate the super-breaker in lieu of 3rd format. My preference is grounded in the belief that the player with better conditioning should typically win close matches because the fitness level is something that is within the player’s control. Considering the stats, I should probably reconsider that stance.
In any case, I am perfectly fine with the WTN treating super-breakers as full sets. I personally believe that those results under pressure are valid performance measures.
- ITA x ITF World Tennis Number Coach Webinar, YouTube Unlisted Video, Recorded January 17, 2023.
- The Science Behind ITF World Tennis Number, ITF World Tennis Number News Post, September 5, 2022.
- Teresa Merklin Player Records, TennisRecord.com, viewed March 24, 2023.
