NEW YORK—Grand Slams are major stumbling blocks for Alexander Zverev.
Philipp Kohlschreiber toppled the fourth-seeded Zverev, 6-7 (1), 6-4, 6-1, 6-3, in the US Open third round on Saturday, continuing some major misery for his Davis Cup teammate.
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The loss came a year after Borna Coric bounced Zverev out of the second round last year. It was the Roland Garros quarterfinalist's third exit from a Grand Slam third round this season.
Players ranging from Roger Federer to Rafael Nadal to Marat Safin to John McEnroe have praised the 21-year-old German as a future champion. But Zverev's US Open exits marks the 12th time in 14 career majors he's failed to reach a Grand Slam fourth round.
So what's holding him back?
Players and coaches point to three factors:
1. His transition game and net play are still works in progress. Zverev won just 20 of 41 net points vs. Kohlschreiber.
2. Zverev can look stressed and play tight in Grand Slams.
3. The 6'6" baseliner can be vulnerable to players who can use the short slice to make him bend and play from awkward spots on court.
While Zverev is supremely fit, he's sometimes strained by the mental grind of major match management and tries to strong-arm his way through points.
"I think maybe the only difference is that it can be very tough in a slam," Kohlschreiber said of Zverev. "You play best-of-five. You play a guy like me, I'm fighting with my last T-shirt, grinding. Maybe that could be a little bit in the back of his head, that it's going to be five sets, it's going to be tough to recover. Maybe sometimes he wants to rush."
Winning Ugly author Brad Gilbert, who coached Andre Agassi, Andy Roddick and Andy Murray, believes when Zverev tightens in Slams his forehand can get spinny and land short in the court.
"When I watch Zverev, for some reason he plays freer when he plays in the thousands and some of the smaller events than he does in the Slams, and when I watch him, sometimes I say so goes his forehand, so goes his chances," Gilbert said. "But I think that he has to forget about the expectations and play the opponent on the other side of the net and avoid playing five-set matches early in the tournament. That's what's kind of gotten him in trouble a little bit the last few Slams."
The 21-year-old German hired Hall of Famer Ivan Lendl as coach before the Open began. Zverev said his new coach is preaching patience as part of the development process.
"He's very straightforward. He said that it's a process of getting there," Zverev said of Lendl. "It's a process of playing well at slams. He told me before the tournament started that, Hopefully you'll do very well at the US Open, but we're more looking towards next year. We're more looking towards being at latter stages, competing for slams next year."
Photo credit: Christopher Levy