Pouille expected to send Schwartzman packing
Muguruza can put down marker with routine success
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Pouille v Schwartzman
Diego Schwartzman sprang the big surprise of the US Open third round by beating fifth seed Marin Cilic 4-6 7-5 7-5 6-4 but he could be brought crashing back down to earth with a defeat to Lucas Pouille in the round of 16.
This is already uncharted territory for Schwartzman, who had previously appeared in the main draw of Grand Slam events on 13 occasions without getting further than the third round.
The Argentinian is an improving player and is having a good year, having appeared in six quarter-finals and one semi-final.
And he will have taken confidence from the win over Cilic, the biggest of his career.
However, Schwartzman was assisted massively by a poor performance from Cilic, who made 80 unforced errors. The Croatian has been struggling with an adductor strain ever since his Wimbledon final defeat to Roger Federer and it showed that day.
A bigger test awaits Schwartzman against Pouille, a consistent performer who has made quiet but steady progress since last year's run to the US Open quarter-finals.
Pouille has appeared in two finals in 2017, winning the Hungarian Open, and his ranking peaked at a career high of 13 in May.
The 23-year-old needs to go deep into the draw in New York, where he did so well last year, to defend his current ranking (20).
Winning the tournament is unlikely but he should go at least one step further.
2pts 4-5 Betway
Querrey v M Zverev
Sam Querrey appeared in the Wimbledon semi-finals for the first time this year but his quest to reach a first US Open quarter-final could be scuppered by big-serving German Mischa Zverev.
Throughout his career Querrey has been a steady player, who has lacked the class and variety to reach the very top.
He took advantage of some good fortune at Wimbledon – defeating a struggling Andy Murray – but his limitations were exposed by Marin Cilic, who defeated him 6-7 6-4 7-6 7-5 in the last four.
Cilic had the necessary power to cause Querrey problems and so does Zverev, a player who is reaching his peak in his early thirties.
Zverev was ranked outside the top 100 for a five-year spell between the summers of 2011 and 2016 but has made huge progress in the last 12 months.
The German was a quarter-finalist at the Australian Open, where he knocked out Murray, and reached the final of the Geneva Open, defeating John Isner and Kei Nishikori on the way.
He also cruised past Isner 6-4 6-3 7-6 in the early hours of Saturday morning and has a good chance of taking a second major American scalp inside three days.
Zverev is value to win the match but it may be worth taking a little extra insurance by backing him with a 1.5-set start on the handicap.
M Zverev +1.5 sets
1pt Evs Betfair, Boyles, Power
Muguruza v Kvitova
Garbine Muguruza was in a class of her own at Wimbledon this year and she can put down a marker at this year's US Open by defeating fourth-round opponent Petra Kvitova in straight sets.
The match is a huge contest for Kvitova, who is bidding to win her first Grand Slam since she was the victim of a knife attack during the winter of-season.
Kvitova sustained tendon and nerve injuries to her left hand but has made a remarkable recovery, winning a grass-court title in Birmingham and reaching the US Open last 16 without dropping a set.
However, she could have done without running into Muguruza at such an early stage of the tournament.
The Spanish player has gained confidence from her performance at Wimbledon and goes into the match with Kvitova having recorded an eight-match winning sequence.
Her latest five victories have been in straight sets, including dominant victories over Karolina Pliskova (6-3 6-2) and Simona Halep (6-1 6-0) in Cincinnati.
Muguruza seems to be playing the best tennis of her career and even a resurgent Kvitova may stand little chance against her.
G Muguruza to win 2-0
1pt 11-10 Betfair, Betway, Power