After placing Kiermaier on the 10-day disabled list, the Rays placed Rickie Weeks Jr. (right shoulder impingement) on the 10-day DL, and transferred infielder Matt Duffy (left heel surgery) from the 10-day DL to the 60-day DL.
In addition, the Rays recalled outfielder Mallex Smith from Triple-A Durham, and acquired infielder Taylor Featherston from the Phillies in exchange for cash considerations.
Kiermaier injured his hip sliding into first base feet-first in the fifth inning of Thursday's 7-5 win over the White Sox at Tropicana Field, and was forced to leave the game.
The six- to eight-week healing timetable, plus whatever additional time Kiermaier would need to work his way back to game action, would place his earliest potential return in August. This spring, the Rays signed Kiermaier to a six-year, $53.5 million contract with an option for 2023, so there's little doubt the Rays will take a conservative stance regarding his return.
Kiermaier missed 48 games last season with a fractured left hand. The team went 14-34 in his absence.
"We saw last year how that affected us, but [we have] a lot of belief in this team that we'll be able to overcome that," Rays manager Kevin Cash said. "I know we're better-suited than we were last year as far as coverage out in center field.
"Mallex Smith is going to come up and play a lot of center field. But even with people like [Peter] Bourjos and Colby Rasmus, guys who have had plenty of reps out there, and successful reps. ... The defense is a lot to us. K.K. brings a different element, but we feel these guys can fill in and do a really good job for us."
Evan Longoria wouldn't go so far as to say the Rays are better fortified this season than last to handle Kiermaier's loss.
"I don't know," Longoria said. "I can't speak to that. It would be easy to say yes, but we haven't gone through it yet. So I would hope that we are. I like the team that we have, I like the players that we have in here. But you just don't know. K.K. is an impact player who has the potential to make a difference both offensively and defensively every day."
Kiermaier, a 2016 American League Gold Glove Award winner and one of the premier defensive outfielders in the game, is batting .258 with seven home runs, 20 RBIs and 10 stolen bases in 62 games this season.
Kiermaier told reporters he didn't expect hear the diagnosis he received.
"I thought it's one of those things, jammed my hip, probably wasn't going to feel good for a little bit but I'd be back out there," said Kiermaier, who noted that he knew right away that he'd broken his hand last season. "This one kind of caught me off guard, but at the same time I knew it wasn't fully healthy, so that's why I took this news a little bit better than I did last year."
Cash said Weeks has not been the same since an early-season collision at first base with the Yankees' Brett Gardner. He added he's hoping the time off will help Weeks return to the form he showed during Spring Training.
As for Featherston, Cash said his versatility will be important to the team during Saturday's doubleheader.
Bill Chastain has covered the Rays for MLB.com since 2004.