"I always take ground balls," Perez said. "I like playing another position."
The idea is to give Yost additional options and versatility and to give Perez an occasional break from the rigors of everyday catching.
"He's played first base in winter ball and he's got tremendous hands," Yost said. "Have you ever watched him take ground balls at short? I've had him take ground balls at first and I just want to see if it's an option. And I'm really convinced it is."
Perez had three hits, including a two-run homer in a 4-1 win, but didn't get much of a test defensively. He caught a foul popup, missed a wind-blown infield pop fly for an error and caught one infield throw.
"Oh my gosh, it was easy over there," he said, joking.
Yost gave up a thumb's up, with one caveat.
"He's going to be fine," Yost said. "It was his first time out there and we definitely need to work on popups in Spring Training next year, but he did fine. He was into it, ready every pitch."
First base is also a way to give Perez's knees a break -- he had knee surgery in 2012 and missed almost half the season -- and perhaps give Hosmer a break against a tough left-handed pitcher.
"You can give Hoz a day off here and there and not lose much on defense. You'll lose some, of course," Yost said.
It's similar to the way that in the past the Twins used catcher Joe Mauer at first base occasionally.
Designated hitter Billy Butler has been the Royals' primary backup option at first base, but he's exhibited some holes defensively.
"If something happens to Hoz in a game and Billy is DHing and you don't want to lose your DH, you've got to have a viable option," Yost added. "[Perez] is going to play a lot of first base in winter ball."
Perez again plans to play a limited time for La Guaira in the Venezuelan Winter League.
"I'm going to play first base, I'm not going to catch," Perez said. "I'll feel comfortable, Hosmer's been teaching me how to play first base."
How's he done?
"Salvy's an athlete, he'll be able to do it, that's for sure," Hosmer said, laughing. "Not like me, but he'll handle it."
Perez was asked why, when some folks consider him the best catcher around, he wants to try first base.
"Why can I not be the best first baseman, too?" he said, laughing.