Pedro Martinez outlasted Lucas Pouille to set up a second-round clash with fellow Spaniard Roberto Bautista Agut at the Generali Open.
World number 97 Martinez came through Monday's longest match, which lasted two hours and 43 minutes, as a 6-3 6-7 (4-7) 6-4 winner.
Mikael Ymer, who reached the quarter-finals of last week's Swiss Open Gstaad, is also through to the second round in Austria after battling past Pablo Cuevas 6-3 7-5.
Qualifier Jozef Kovalik will face Jiri Vesely for a place in the quarter-finals, meanwhile, after beating ninth seed Jaume Munar in straight sets.
Also through on Monday was lucky loser Carlos Taberner, who took advantage of his second chance by battling from a set down to overcome Thiago Seyboth Wild 3-6 6-3 6-2.