After Epic Comeback, del Potro Hopes to be Fully Healthy for Federer Showdown

Juan Martin del Potro staged one of the U.S. Open's most remarkable comebacks on Monday.

Juan Martin del Potro's miraculous comeback Monday against Dominic Thiem will go down as a U.S. Open classic. A clearly ill del Potro struggled during the first two sets, dropping them 6-1, 6-2. But with most of the Grandstand loudly cheering him on, del Potro improbably stormed back to win the match in five sets. 

Del Potro's reward? A quarterfinal match against Roger Federer, who has stepped up his game after a shaky start to the tournament. Del Potro famously upset Federer in the 2009 U.S. Open final, but after a five-set marathon, the Argentine will need to turn in another great performance to knock out the No. 3 seed. 

As if playing Federer wasn't enough, del Potro's fitness remains a potential concern, particularly after grinding through five sets. Though his illness only makes his Monday comeback more impressive, he'll need to recover quickly physically to give Federer his best shot. 

Del Potro admitted after Monday's match that he was considering retiring in the second set. 

"I was thinking to retire in the middle of the second set because I couldn't breathe, I couldn't move well," del Potro said. "Dominic was dominating the match so easy." 

Del Potro told Pam Shriver, who interviewed him on-court after Monday's match, that he had been sick for two days. 

Federer and del Potro will meet in the second match of Wednesday's night session, meaning del Potro will have a full 48 hours to recover after his marathon match against Thiem. 

"Hopefully my day off [Tuesday] I can recovery a little bit more," del Potro told reporters following his match. "Then I will see if I'm ready to play in good conditions against Roger." 

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Whether del Potro is fully healthy remains to be seen, but Federer is looking forward to the rematch of the 2009 final. 

"I'm really happy for him," Federer said. "It's a good match to look forward to...I hope we can produce another good one."