Sam Querrey was given a scare in the first round of the ATP Abierto Mexicano Telcel in Acapulco before beating wildcard Tigre Hank in three sets.
Local favourite Hank took the first set on the tiebreak before Querrey broke the 646th-ranked Mexican in the first games of the next two sets to prevail 6-7 (5/7) 6-4 6-3.
The American will next take on the winner of the clash between France's Stephane Robertson and Kevin Anderson of South Africa.
The other first round encounters were much more straightforward, with Israel's Dudi Sela beating Columbian qualifier Alejandro Falla 6-1 6-4 to set-up a meeting with either third-seeded John Isner or Ivo Karlovic in the next round.
France's Jeremy Chardy took just over an hour to see-off Matthew Ebden of Australia 7-5 6-0 and will next take on eighth-seeded Vasek Pospisil or Alexandr Dolgopolov.