Brian Baker won a topsy-turvy battle against Alex Bogomolov Jr to make the second round on his Australian Open debut.
The American made his career breakthrough at Wimbledon last year and started strongly in Melbourne, taking the first two sets in a battle dominated by baseline exchanges.
Bogomolov hung on with a spirited performance in the third-set tie break, not allowing Baker a single point to keep the match alive.
Baker wobbled on serve in the fourth, tightening up to allow his opponent to level the match at two-sets apiece.
Deep in the fifth Baker regained his form, securing a hard-fought break of serve before punishing his opponent to get over the line 7-6 (7-4) 6-3 6-7 (0-7) 3-6 6-2.
Baker had taken the best part of six years off the tour due to persistent injuries but continued his battle to make up for lost time to set up a potential clash with compatriot Sam Querry in round two.