US Open Women's Singles Day 8 Tips: Swiatek exit the main talking point

• Swiatek loss sees outright market transform

• Vondrousova expected to ease into quarter-finals

• Markets defensive on Jabeur's chances

Gauff favourite following Swiatek shock

Jelena Ostapenko's shock win over Iga Swiatek has created a big change in the tournament winner market, with Cori Gauff now edging favourite status at 4.03/1 ahead of Aryna Sabalenka 4.57/2.

While Sabalenka was ahead of Gauff pre-tournament in this market, the exit of Swiatek means that Gauff doesn't have to play her in the next round, which makes the market movement make more sense.

Vondrousova and Sabalenka strong favourites on Monday

Action gets underway on Monday at 16:00 UK time, with Marketa Vondrousova expected to ease past Peyton Stearns, who got the better of Brit Katie Boulter in the previous round. The duo actually met earlier this summer at Wimbledon in round one, with Vondrousova easing to a straight-sets win priced around the 1.282/7 mark, so the Czech is a shorter price here than that day at SW19.

In terms of hard court data, Vondrousova looks well-placed to inflict a similar result. Her serve data, in particular, is far superior and Stearns is going to have to play very well in order to have upset potential.

Tournament second-favourite Sabalenka is the other player expected to get into the quarter-finals, currently trading at 1.331/3 against Darya Kasatkina. Sabalenka defeated her opponent 6-3 6-3 in Cincinnati several weeks ago, and her serve is so far superior to Kasatkina's that it is really difficult to dispute market lines.

Jabeur struggles create market caution

The other two matches remaining in the fourth round look far more competitive on paper. Ons Jabeur has a marginal market edge at 1.794/5 against the Chinese prospect, Qinwen Zheng, with the market a little cautious on Jabeur given her continuous battles to get through to this stage.

The Tunisian has needed three tiebreak wins to avoid difficult situations in matches, particularly against Marie Bouzkova last time out and it's probably fair to say that Jabeur hasn't convinced so far here in New York. Zheng's recent losses have been against strong opposition (Swiatek, Samsonova, Keys), and the market looks accurate here for this match-up at this time.

Pegula justified favourite over Keys

Finally, Jessica Pegula is favourite at 1.594/7 against fellow American Madison Keys, having came through a tricky clash with Elina Svitolina in round three.

Pegula came into the event in good form, winning in Montreal and having beaten Gauff and Swiatek there, and looks like a justified favourite at a similar price to their last clash towards the end of last season, also on hard court.