ATP Masters first round outsiders
The first round of a Masters draw is where ranking is least informative, and where the market leans on it hardest. Three prices we think are wrong.
A Masters first round is usually a seed against somebody who came through qualifying, and the market prices it largely off ranking. Ranking is a twelve month rolling total, which makes it a good summary of a career and a poor summary of a fortnight.
Where the lag lives
A qualifier who has won eleven of thirteen matches in the last month, mostly at a lower level, carries a ranking that reflects the eleven months before that. Our point model reads the recent matches directly, weights them for the level they were played at, and often lands on a serve-and-return estimate several points away from where the ranking implies.
Because the scoring system amplifies point-level differences, several points on serve is a large gap in the match price.
The three this week
The widest is a qualifier priced at 5.50 where our number sits nearer
4.20. Two things drive it: a surface switch that suits his game and a seed
who has played three consecutive weeks and travelled between two of them.
The second is a 3.80 against a seed returning from six weeks out. The market
has discounted the layoff. Our research half found the return date but no
practice reporting, and where evidence is absent the number stays close to the
model rather than moving on a guess.
The third is closer, at about two points, and is included because the price drifted after the draw was made without any news we could find. A move nobody can explain is not automatically wrong, but it is worth writing down.
What this does not tell you
Longer prices carry more margin, so an outsider has to be more wrong to be worth the same as a favourite being wrong. And a first round has no in-event information at all: the first genuinely well-informed tennis market of any tournament is the second round.
Common questions
Why are first round tennis matches hard to price?
Because they often pair a seeded player with a qualifier whose recent form is on a different surface, at a different level, and against opponents the ranking does not describe.
Is ranking a good predictor in tennis?
It is a decent one and a lagging one. A ranking is a twelve month rolling total, so a player who has improved sharply in the last two months is underrated by it.
Do outsiders offer value more often than favourites?
Not systematically. Longer prices carry more of the bookmaker's margin, so an outsider needs a larger genuine edge to be worth the same.