LONDON — Juan Martin del Potro faces some major challenges if he's going to go any further at Wimbledon after reaching consecutive Grand Slam quarterfinals for the first time since 2012.
First, on Wednesday he'll take to the court for a third consecutive day amid concerns over his fitness. Second, his opponent will be two-time Wimbledon champion Rafael Nadal.
2009 U.S. Open champion Del Potro defeated Gilles Simon 7-6 (1), 7-6 (5), 5-7, 7-6 (5) in a match that was carried over to Tuesday to complete the men's quarterfinal lineup at the All England Club.
The other matchups see defending champion Roger Federer against Kevin Anderson; Novak Djokovic takes on Kei Nishikori and Milos Raonic meets John Isner in a matchup of big servers.
After reaching the French Open semifinals last month, Del Potro — who has missed long periods with a career-threatening left wrist injury — returned to his career-high ranking of No. 4 for the first time since February 2014, which he acknowledges is a "good signal".
"I don't know if I'm better or not, a better player than few years ago," said Del Potro, after returning to the last eight at Wimbledon for the first time since 2013. "I'm doing a good season already. I'm very proud to be in the last eight players of this tournament"
Del Potro's Roland Garros run was ended by eventual champion Nadal. If the Argentine is to make it back-to-back last four appearances, he will need to reverse that result on Wednesday.
"If I want to beat him (Nadal)," Del Potro said. "I have to come to the net very often and play hard with my forehands, with my backhands, and try to take all the chances."
With the fifth-seeded Del Potro's fourth-round match — the longest men's singles contest of the tournament so far — having required to be finished Tuesday, he will be taking to the court for a third consecutive day.
Given the fact he withdrew from a pre-Wimbledon event with a groin concern and called the trainer during his match with Simon, Del Potro's fitness could be a factor.
"I think I will be in good condition." Del Potro said. "My body feels OK."
There is little doubt that Nadal — who is playing in the Wimbledon quarterfinals for the first time since 2011 — will provide a big test.
Before Del Potro and Nadal arrive on Centre Court, three-time champion Novak Djokovic, will get the chance he's been waiting for.
Having played three of his matches away from Centre Court, Djokovic asked after his fourth-round win over Karen Khachanov that his meeting with 24th-seeded Nishikori be played in the main stadium.
His wish was granted, meaning that top-seeded Federer will play away from Centre Court for the first time in three years.
The more gusty conditions on No. 1 Court could make Federer's challenge against eighth-seeded Kevin Anderson more complicated.
Stretching back to last year, Federer has won 32 consecutive sets at Wimbledon and will break his previous longest streak of 34 if he wins in straight sets.
Following Federer on No. 1 Court will be the two biggest servers remaining in the tournament.
Ninth-seeded Isner has hit a tournament-high 135 aces on his way to reaching his first Wimbledon quarterfinal. Next in the aces column is his opponent, 2016 runner-up Raonic.
The 13th-seeded Raonic has hit 117 aces en route to his fourth last-eight showing at the All England Club.
Both players said the match is likely to come down to a few crucial points, but took different tones when asked to suggest where they might have an advantage.
"I think I can move a little bit better than he can," Raonic said.
Isner's retort: "I'm taller than him. That's all I got for you right now."