NEW YORK (WFAN/AP) — Defending champ Rafael Nadal took full advantage of a fresh start, dominating Gilles Muller when their rain-delayed match resumed at the U.S. Open.

The second-ranked Spaniard was down a break, trailing 3-0 when play was stopped after 15 minutes Wednesday.

He went on to win 7-6 (1), 6-1, 6-2 after they took the court Thursday, completing a fourth-round match that was supposed to start two days earlier.

The 68th-ranked Muller had not faced a seeded player in his first three matches. The lefty from Luxembourg reached the quarterfinals at the 2008 Open as a qualifier for his best performance at a Grand Slam, then was sidelined by a knee injury.

Nadal was coming off treatment for painful leg cramps during his post-match news conference Sunday, then was frustrated Wednesday that tournament officials tried to start play in less-than-ideal conditions.

He still faces a tough road to defend his title, potentially having to play four matches in four days.

Does Nadal have the stamina to take home the US Open title? Sound off in the comments below…

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