ST. LOUIS -- Royals All-Star center fielder Lorenzo Cain was placed on the 15-day disabled list on Wednesday with a strained left hamstring, and outfielder Brett Eibner was recalled from Triple-A Omaha.
Royals manager Ned Yost said the MRI taken on Tuesday night showed Cain has a Grade 1-plus strain. The club's training staff indicated it was between a mild and moderate strain.
Both Cain and Yost said Cain could be ready to be activated by the Friday after the All-Star break.
"Hopefully it won't be more than the 15 days," Yost said.
Added Cain, who made the trip to Busch Stadium, "That's the plan. It just depends how it feels. I'm very optimistic about the MRI we saw. Hopefully I'll be ready to go right after the All-Star break."

Cain sustained the injury as he was trying to leg out a ground ball in the seventh inning against the Cardinals on Tuesday night at Kauffman Stadium.
"I was definitely shocked when it happened," Cain said. "My legs had been feeling really good when it happened. I touched the bag and tried to slow down, and that's when I felt it. It shocked me at first, but that's part of the game."
"I felt it. I was just hoping it wasn't really bad. The MRI showed it wasn't a complete tear. That's always good. I'm happy it is not worse than it is."
The timing is bad for the Royals, obviously, as they launch an eight-game road trip and were 13-25 on the road entering Wednesday.
"We'll find a way to cover it," Yost said of replacing Cain. "We've got [Jarrod] Dyson or Paulo [Orlando]."
The timing also wasn't good for Cain, who is in the hunt for the final starting outfield spot in the All-Star Game presented by MasterCard. Cain is fourth in the fan balloting, which ends on Thursday night at 10:59 p.m. CT.
Even if voted in, Cain won't be able to play.
"I definitely wanted to be a part of that, but won't be able to," Cain said. "I just have to get healthy and make a push in the second half."