"That ball was smoked and it was a crazy play," manager Scott Servais said. "We got very, very fortunate. He hasn't had a lot of reps over there either, but he should be fine."
• Spring Training: Tickets | Schedule | More
Romero, 27, had walked and singled in his two at-bats after belting a home run in Wednesday's Cactus League opener.
Romero played first and third base at Oregon State, but he shifted to second after being selected by Seattle in the 2010 Draft, and then he transitioned to the outfield in '13. The Mariners are looking for a right-handed platoon partner for Adam Lind at first base and want Romero to work into that mix along with Jesus Montero, Dae-Ho Lee and Gaby Sanchez.
Veteran Efren Navarro, who joined the Mariners on a Minor League deal on Wednesday, moved from left field to first base to replace Romero, with utility infielder Luis Sardinas taking over at third as Shawn O'Malley shifted from third to left.
The end result was Sardinas getting a chance to belt a pair of two-run doubles on a day he wasn't even expected to play.
"I'll be ready every time, if something happens," said Sardinas, a 22-year-old Venezuelan competing for the utility infield role. "That's part of it. If I make the team, I need to prepare every day for playing."
• Servais said Cuban center fielder Guillermo Heredia will likely get into a Cactus League game in the next few days after joining the team on Wednesday following nearly a two-year layoff since his defection to Mexico.
"He moves really easily in the outfield," Servais said. "Going off our scouting reports, he's a plus-plus defender. I've talked to Edgar [Martinez] a little bit and the hitting guys that have seen him in the cage. There's bat speed there. He just hasn't played in a competitive game in awhile."
• Lee was not with the team on Thursday as he's taking care of a work visa situation, but the Korean slugger should rejoin the Mariners "very, very soon," according to Servais.
• Closer Steve Cishek saw his first action and pitched a scoreless fifth, though he gave up a single and hit a batter. Justin De Fratus, a former Phillies right-hander who signed a one-year deal, gave up a run on back-to-back doubles in the seventh, but then came back and pitched a 1-2-3 eighth. Servais said De Fratus will likely be used in multiple-inning roles if he makes the club.