Sixth seed Feliciano Lopez came through a tough test to beat Sam Querrey at the Delray Beach Open.
Lopez lost the first set to world No 57 however he recovered to register a 4-6 6-2 6-3 victory in 94 minutes.
Lopez, ranked 27 in the world, was slow out of the blocks as he was broken twice in the opening set - although the Spaniard did win one of the five break points that he fashioned.
The second set was a different story, though, as Lopez moved through the gears - dominating his own service game and breaking the American twice en route to levelling the match.
Querrey just couldn't find a way to turn the match in favour and when he was broken for a fifth time the writing was on the wall.
Lopez will now face Adrian Mannarino after the Frenchman also ousted wild card Jack Sock.
Mannarino, the world No 70, barely got out of first gear as he won 6-4 6-2, although he didn't have things his own way as he saved seven break points.