Guillermo Garcia-Lopez fended off a spirited second-set fightback from Michael Berrer to book his place in round two of the Estoril Open.
Veteran Spaniard Garcia-Lopez, a five-time victor on the ATP tour, came through 6-3 7-6 (7-3) on the Portuguese clay.
However, Garcia-Lopez had difficulty in seeing out the win, with Berrer clawing back a 5-1 deficit in the second to force a tie-break, but the fifth seed regained his composure to progress.
Fellow Spaniard Daniel Gimeno-Traver was a faller at the first, though, the world number 143 beaten 6-3 7-5 by Kyle Edmund.
Rogerio Dutra Silva was a 6-4 6-1 winner against Benjamin Becker, Inigo Cervantes dispatched fellow Spaniard Daniel Munoz-Dela Nava 6-4 6-1, Taro Daniel ousted Steven Diez 7-5 6-1 and Paul-Henri Mathieu comfortably beat Gastao Elias 6-3 6-4.
Paolo Lorenzi saw off qualifier Elias Ymer 7-6 (7-4) 6-3 in the final game of the day.