LOS ANGELES -- Los Angeles Dodgers manager Don Mattingly said it was nerves, not a physical ailment, that contributed to starter Hyun-Jin Ryu's shaky start in Game 3 of the National League Division Series against the Atlanta Braves on Sunday night.

"He was fine," Mattingly said of Ryu. "There were no restrictions on him tonight. If there had had been anything physically wrong, we wouldn't have let him pitch today."

Ryu lasted only three innings in his postseason debut. He was lifted after giving up four runs, six hits and throwing only 68 pitches, but the Dodgers went on to win, 13-6.

"It seemed like he had trouble getting settled in," Mattingly said of Ryu. "Usually with him there's more swing and miss. His velocity was OK. It seemed like he touched 93, and we've seen him starting out at 90-91. He just didn't seem to have that same finish and to be able to locate. It was just one of those rough nights."

Questions had emerged about Ryu's health when Dodgers team doctor Neal El Attrache watched him throw a bullpen session on Friday. Ryu said that session was simply to stay sharp with the long layoff, but Dodgers broadcaster Vin Scully suggested during Sunday's broadcast that Ryu was dealing with elbow and back issues.

Ryu disputed that notion as well.

"There was absolutely no injury whatsoever," Ryu said. "There was anxiety and I was a little bit nervous taking the mound.

"But I think the earlier part of the game when I had the count going my way, I think I should have honed in and focused a little more. That's the mistakes I made."