Santiago Ventura also advanced when Alberto Martin retired with a left leg injury when leading 5-4 in another second-round match.
Ventura will play Ruben Ramirez Hidalgo, who beat Romanian wild card Marius Copil 6-3, 6-7 (3), 6-4. The 18-year-old Copil served 11 aces.
In the first round, eighth-seeded Pablo Cuevas of Uruguay edged Andrei Pavel 6-3, 7-6 (2) to end the Romanian's career.
"I dreamed of ending my career in Bucharest," said Pavel, who will stay on as captain of Romania's Davis Cup team. "I am a bit sad because of this defeat, but now the rankings do not matter anymore - what matters is the joy of playing."
Simon Greul of Germany beat Steve Darcis of Belgium 7-5, 6-3 in another first-round match.
Primera Liga round-upShvedova, Peer advance at Tashkent Open
