Sam Querrey through in four sets

American seed Sam Querrey survived an early scare on day one of the Australian Open to set up a second-round clash with compatriot Brian Baker.

World number 174 Daniel Munoz-De La Neva enjoyed a bright start on his second appearance in Melbourne, matching Querrey to force a tie-break in the first set.

The Spanish qualifier turned on the style in the breaker, winning 7-2 to claim the opening set and stun the 20th seed.

Querrey went back to basics in the second set and found an immediate response, leveling the match with a single break.

De La Neva's fine start was a distant memory in the third, with Querrey finding form to take the lead.

Querrey showed his superiority in the fourth to take the match 6-7 6-4 6-2 6-4 and create an all American clash with Baker, who won a five-set thriller against Alex Bogomolov Jr earlier today.