Navarro said he sustained the injury during the seventh inning of Tuesday's 13-6 win when he tried to stretch a deep single to center into a double.
"I felt the pop right before I was going to slide into second base," Navarro said. "In the back of my mind I had the slightest hope it wouldn't be that bad, but I kind of knew. I've been through this before. I'll just go through my treatment and get back as soon as possible."
The injury couldn't have come at a worse time for Navarro, who's been splitting duties as the club's designated hitter and backup catcher. Navarro went 3-for-5 in Tuesday's series opener to raise his season average to .267 with a pair of doubles.
"It's just part of the business," Navarro said, when asked whether he's disappointed given the timing of the injury. "The only person who doesn't get hurt is the one who doesn't play."
Catcher Josh Thole was recalled from Triple-A Buffalo on Thursday to take Navarro's place on the roster. Gibbons said Thole will likely catch Friday's series opener against the Tampa Bay Rays, though he attributed it more to do with rest for Russell Martin and not because knuckleballer R.A. Dickey is on the mound.
"We've got a night game tonight and then long travel, we're going to get [into Tampa Bay] late, and you still want to get Russ fresh," Gibbons said. "We've got to do what's best for him, too, so yeah you'll probably see Thole there [Friday]."
Gibbons said moving forward he'll let opposing matchups dictate who's behind the plate in order to maintain flexibility in his lineup. He said it helps that Martin's had success catching Dickey's knuckleball early this season.
"Perfect example, if Thole starts [Friday] and we get to that part of the game where we need something done at the plate and Russ is our best option, then we can hit him there and not worry about losing Dickey."