It's quarter-final day in the two WTA Tour events this week and with some intriguing matches in prospect, our tennis columnist Dan Weston discusses the schedule...
"Teichmann has dropped just 11 games and won both matches in straight sets so far to get to this stage, but a closer examination of those matches suggests she's been fortunate to win so comfortably - she's only had two more break points than her opponents in those matches combined."
Serena needing three sets to defeat sister Venus
In yesterday's action, Serena Williams again stumbled into victory with the Lexington top seed needing a comeback win to get past sister Venus. A look at the match stats, however, tells a slightly different story, with Venus facing 15 break points and saving 10 - it was key point performance for Venus that kept the match as close as it was. In the first set, which Venus won, she saved break points and held in two service games, while breaking Serena twice from three opportunities. It's those fine margins which dictate scorelines and, in some cases, matches.
We also saw CiCi Bellis and Shelby Rogers get decent victories on the Lexington hard court, while Jill Teichmann surprisingly got the better of Yulia Putintseva. More on Teichmann later.
Bogdan should compete despite negative head-to-head
However, as has been the case this week, action begins at 10am in Prague and Simona Halep was another top seed who just about made it to this stage having been a set and break down early in the second set against Barbora Krejcikova. Today, Halep faces Magdalena Frech and even as a [1.25] heavy favourite, I think this price is some slight value.
The other small value spot in Prague is Ana Bogdan who, despite a random 5-0 head-to-head deficit, doesn't look a bad price at [2.98] against Krystina Pliskova. Bogdan should be well rested following Lesia Tsurenko's withdrawal from their second round match and the head-to-head is reasonably competitive. Bogdan's games won percentage isn't a disaster in these, and would be much more than I'd expect for a player who has lost five from five head-to-head matches.
Jabeur slight value against overperforming Gauff
It's in Lexington, though, where I feel there is more value and our initial discussion takes us to some of the later matches.
From a win-loss perspective, Cori Gauff has had a fantastic start to her WTA career, but there are more questions than answers provided by her underlying data which should be put into some sort of context. Across all surfaces in the last 12 months, she's winning around three-quarters of her matches, but this is despite winning just over 101% combined serve/return points won. A strong tiebreak record certainly helps, and having won not much more than 50% games in these clashes, it would suggest that she's won a number of very tight matches.
It's important to point out that around a 101% combined serve/return points won percentage is spectacular for a 16-year-old and implies that Gauff has the potential to be a future superstar, but it's not equivalent to such a high win percentage, and such a discrepancy often tends to be down to fine margins and variance - it's extremely difficult to outperform service/return points won expectations in the long-term.
Today, Gauff takes on the capable Ons Jabeur, who actually has pretty similar stats in the last year or so - yet the Tunisian is the underdog at [2.22].
Bouzkova an interesting underdog against Brady
Another match where I'm slightly struggling to understand the market price is Marie Bouzkova at [2.56] against Jennifer Brady. Both players are around a career best ranking just inside the top 50 and the Czech, Bouzkova, has slightly better hard court data over the last year. I wonder how much Brady's semi-final in Dubai just before lockdown, where she had good wins over a few top 20 players, and a decent run in Brisbane, where she beat world number one Ash Barty, is influencing the market.
However, Bouzkova reached the final in Monterrey in the last main tour event before the WTA Tour paused, beating Jo Konta and losing a very tight final to Elina Svitolina, so she's also produced a solid level this year so far - I'm interested to see how Bouzkova fares here.
Bellis should have too much for Teichmann
Despite this, I want to look at CiCi Bellis as our choice today. I'm so pleased to see Bellis picking up wins after injury stalled an extremely high potential career for several years, and she's progressed past Francesca Di Lorenzo and Jessica Pegula for the loss of just eight games so far here in Lexington.
In today's quarter-final, Bellis is favourite at a current [1.53] against the Swiss clay-courter, Jill Teichmann, who I'm very surprised to see at this stage having really struggled on hard courts in the last year or so, until this week.
Teichmann has dropped just 11 games and won both matches in straight sets so far to get to this stage, but a closer examination of those matches suggests she's been fortunate to win so comfortably - she's only had two more break points than her opponents in those matches combined.
When I priced up the match, I was expecting to see Bellis priced around [1.35], and was extremely surprised to see this market line. Either taking this as just a match result price, or the bigger price on Bellis -2.5 games, which should settle at around [1.70] as the handicap market becomes more liquid, looks absolutely reasonable.
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Back CiCi Bellis at [1.53] to beat Jill Teichmann