To make room on the 40-man roster, the Royals placed infielder Miguel Tejada on the 60-day disabled list, effectively ending his season. A corresponding move to clear a spot on the 25-man active roster was pending.
Although manager Ned Yost was optimistic that Moustakas would not go on the 15-day disabled list, he's not expected to be game-ready immediately.
"I'm thinking, best-case scenario, maybe have him to do some pinch-hitting or playing maybe Saturday or Sunday," Yost said. "We'll just have to wait and see."
After Wednesday's 5-2 loss to the Marlins, Yost indicated that Bonifacio or the team's other recent acquisition, Jamey Carroll, were the likely candidates for third base at Detroit. Elliot Johnson not only had defensive problems at third base on Wednesday, but is in a 0-for-31 slide.
Bonifacio, 28, batted .218 with three homers and 20 RBIs in 94 games for the Blue Jays. He's previously played with Arizona, Washington and Miami. His best year was 2011, when he hit .296 for the Marlins.
"He's very versatile. He can play multiple positions -- infield, outfield. He can play second base, third base, all three outfield positions and is a switch-hitter," general manager Dayton Moore said. "He has speed as well."
Bonifacio has 122 stolen bases in 156 attempts (78 percent) in his career.
The trade brings him into the same organization as his younger brother, Jorge Bonifacio, an outfielder with the Royals' Double-A club at Northwest Arkansas. He is ranked as Kansas City's No. 5 prospect by MLB.com.
The Royals picked up Carroll, 39, from the Twins on Sunday, but initially indicated he would platoon with Chris Getz at second base.
The Royals have lost center fielder Lorenzo Cain, as well as Tejada and Moustakas, to injury recently.
Moustakas came out of Monday night's 6-2 win over the Marlins with tightness in his left calf and hasn't played since.
"I'll be ready as soon as they tell me I'm ready to go," Moustakas said. "I feel like I can go out and play every day, but obviously right now I'm not able to and it hurts not being able to go out there with the boys and help out."
Moustakas reported to Kauffman Stadium on Wednesday wearing a boot on his left foot.
"It takes pressure off his calf, it's a precautionary thing," Yost said.
Yost had a brief scare in the seventh inning on Wednesday when catcher Salvador Perez took another foul shot to the mask. He had missed a week with a low-grade concussion and just returned on Sunday.
"He took it off the forehead. The other two he took was off the chin, and this one was more off the top of the head," Yost said. "But he's fine, turned out OK, no problems. But it did make me a little nervous at first."
On Wednesday, Perez went back to his usual mask after trying a hockey-style mask for two games.