Schwartzman will take the result as a confidence booster having lost four of his previous five matches on Tour.
He will next face German qualifier Daniel Masur, who recorded his first Tour-level victory of the season by defeating Maximilian Marterer 6-3 6-4.
Defending champion Leonardo Mayer looked impressive as he raced past Spain's Albert Ramos-Vinolas 6-3 6-2 in 83 minutes.
Fourth seed Damir Dzumhur, ranked 24th, struggled with his serve and was broken four times in a shock 6-2 6-4 defeat by Slovakian qualifier Jozef Kovalik.
It was Kovalik's highest-ranked win since he overcame then world number six Marin Cilic at Chennai in January last year.
(Reporting by Hardik Vyas in Bengaluru; Editing by Christian Radnedge)
