Three to See: 2015 U.S. Open, Day 5

Before each day's play at Flushing Meadows, we'll preview and predict three must-see matches.

Here’s one of the more surprising head-to-heads: Williams and Bencic have played three times, and Venus has won all six sets—6-1, 6-2, 6-4, 6-1, 6-3, 6-1. It’s true that Bencic is still a teenager, and that one of those matches was played in 2012, when she was 15, but there’s something about this matchup that has decisively favored the veteran so far.

Still, if there’s a match when you would expect Bencic, who is ranked 11 spots higher than the 35-year-old Venus right now, to start turning that around, it’s this one. She won a big title last month in Toronto, and beat a lot of quality players to do it. Meanwhile, Venus got tight trying to close out her match against Irina Falconi in the second round. It will only be tougher against Bencic, who is a much better opponent, and who saved three match points on Wednesday. Winner: Bencic

If there’s ever a take-the-next-step match for Keys, it’s this one. Four times she’s played Radwanska, and four times she’s lost. But in the biggest of them, at Wimbledon in 2013 and 2015, the hard-hitting American pushed the higher-ranked Pole to three sets.

This year at Wimbledon Keys seemed to be in control after taking the second set, but she couldn’t keep the winners flowing all the way through the third. And that’s what makes this an especially important test for Keys: Against the underpowered but thoughtful Radwanska, the match will be on her racquet. Keys, playing at home, is due, but Aga will make her earn it. Winner: Keys

Until this year, Fognini appeared to be an unlikely challenger for Nadal. The Italian is a natural ball-striker, yes, but he didn’t seem to have the stomach for the long fight that’s typically needed to wrestle Rafa down. But the Fog proved up to the job in Rio this winter, when he came back from a set down to beat Rafa 7-5 in the third. Two months later, he followed that up with a straight-set win in Barcelona, before Nadal turned the tables back in Hamburg in July.

Those contests were on clay. How will they match up on hard courts, at night in New York? Rafa has played decently in his first two rounds, but has continued to look vulnerable. We’ll see if Fognini is in the mood to take advantage. Either way, it will be interesting to see how the New York night crowd takes to Fabio, and how Fabio takes to the New York night crowd. Winner: Nadal