Against the Giants on Saturday, Villanueva went three innings and gave up one run on one walk and four hits, including a solo home run by Pablo Sandoval.
"I felt better in the third inning," Villanueva said. "The first two innings, it was like my first outing. The last time, I didn't get a chance to work through my mechanics. The first two innings today, even though I got good results, it was still kind of adjusting.
"That's why we're here," he said. "I'm satisfied, even with the home run allowed. It's the best I've felt, and I had better rhythm that [third] inning. Sometimes you have to tip your cap. I'd rather tip now in spring than in the regular season. It's a better day but I still have work to do."
Villanueva has been used as both a starter and reliever, and has been asked a lot this spring about which he'd prefer. Garza will likely miss at least the first regular-season series as he recovers from a strained lat, and Baker wasn't expected until mid-April as he recovers from Tommy John surgery.
All Villanueva did this offseason was prepare to pitch as much as needed. He's rooting for Garza, Baker and everyone on the roster to be healthy. He says he'll do whatever manager Dale Sveum and the front office ask because "I'm an employee here, and whatever I can do to make the seven guys behind me feel like we have a chance to win that day, then I'll do it."
Demanding to start isn't part of his makeup.
"I feel that's more of a selfish way to think, and I try to shy away from that," he said. "This is the definition of a team sport in baseball, and we don't want anybody in the clubhouse thinking for themselves. Those are not playoff teams, those are not championship teams."
He pointed out that not many people picked the Giants to win the World Series last year.
"You don't hear anything out of their clubhouse that would be damning to their chemistry," Villanueva said. "That's what we're building for, and I think we have a bunch of guys whose personalities fit that bill."