"We've had probably more moves than I've ever had as a manager this early into the season," manager Jim Leyland said Wednesday.
Another Tigers catcher, Gerald Laird, is among the walking wounded, dealing with his own right hamstring tightness to the point that he was noticeably hobbling on his way around the bases in the ninth inning of Tuesday's 4-2 loss to the Indians.
Laird was available only in an emergency Wednesday. He was still hobbling went he went behind home plate to catch Tigers pitchers between innings, and when he went out to the bullpen later.
Laird had entered Tuesday game to replace Avila, whose first start since last Friday aggravated the hamstring injury that had sidelined him.
"I'm assuming I did it when I came in on Friday," Avila said of the injury. "I just didn't feel anything and I woke up with it on Saturday. Normally when I get injured during the game I don't feel it. You're adrenaline is pumping, things like that. I didn't have a definitive moment like Laird did running on the bases or anything, but I guess sometime it happens that way."
One big reason Avila sat over the weekend was the worry that playing and tweaking the hamstring would cause a worse injury and a longer absence. This was pretty much the scenario that played out.
"It's part of the game," Avila said. "It happens to guys at some points in their career and you just got to be able to deal with it."
Avila threw out Shin-Soo Choo trying to advance to second on a pitch in the dirt to end the fifth inning, but was seen hobbling as he made his way back in the dugout. He promptly went down the tunnel towards the clubhouse.
Realistically, though, Avila said he'd been dealing with the tightness for most of the game.
"It was pretty tight, probably from the second inning on," Avila said. "I started feeling it. It never really got loose. On that [throw], I really felt it pull and figured that right about there, I couldn't really push it anymore."
An MRI exam taken Tuesday night confirmed a strain, rather than any tear. Avila said he was told that he would need 10-14 days to heal. The 15-day DL should fit that timetable nicely.
"I'd rather it be like a two week thing that it's going to be now," he said, "rather than I tear my hamstring and it's a month to a month and a half."
Holaday is known as a defensive presence behind the plate. The 2010 Tigers draft pick batted .248 at Triple-A Toledo with six doubles and 10 RBIs in 121 at-bats. He has thrown out 15 out of 39 would-be basestealers for a 38 percent caught stealing rate.
"He's got a lot of energy," Leyland said. "He's a very good receiver and a very good thrower. I don't expect him to be the guy to turn around offensively. I just want him to handle the pitchers. But I like Holaday. He's a fiesty kid."
With Laird out, Holaday started Wednesday and recorded his first Major League hit. He'll likely continue starting into the weekend until Laird is close enough to full strength to move around without pain.
"I think in the next three or four days, I'll be 100 percent," Laird said. "But if [Leyland] needs me to play, I can go."
Santos started two games behind the plate over the weekend while Avila and Laird were both sidelined. He provided a game-winning sacrifice fly Saturday night, but had been struggling with stolen bases.
Holaday's call-up triggered a shuffle of the Tigers' catching prospects, with highly-valued catching prospect Rob Brantly heading to Toledo. James McCann, last year's top Tigers draft pick, will take over at Erie after being called up from Class A Lakeland.