INDIANAPOLIS — The Indianapolis Colts believe lingering pain in Andrew Luck's lower left leg will likely force their starting quarterback to miss the rest of the preseason.
They're still unsure about his availability for the Sept. 8 season opener against the Los Angeles Chargers.
Colts general manager Chris Ballard said Tuesday additional testing revealed Luck appears to be suffering from an injury near the front of his ankle, something his previously diagnosed strained left calf might have exacerbated.
"Honestly, I think it's a cumulative thing through the years. Andrew's had some issues with his left (ankle) for a while, so I think it's really a cumulative thing," Ballard told local reporters on a conference call. "We think we've found it. You hope you've found what the cause is. Is there a 100 per cent guarantee? No, but we think we have, so we'll move forward and try to treat it."
The injury kept Luck out of all of the team's off-season workouts and all but three training camp practices. He still has not participated in full team drills.
Ballard and coach Frank Reich initially described the injury as a strained calf, but when Luck continued to complain about soreness, team officials started digging deeper to get answers.
On Monday, Colts owner Jim Irsay told SiriusXM radio the team believed Luck had an injury to the os trigonum, a small, accessory bone near the back of the ankle.
But new tests, Ballard said, determined the soreness was coming from the front of the ankle.
"Most of his pain is right below the calf, kind of anklish, up a little bit. Remember, everyone kept focusing on the Achilles and it's not the Achilles," Ballard said. "The issue right now is the side to side stuff, the rolling of the ankle. Anything moving forward is good. It's the moving in the pocket."
In his most recent interview, Luck said he felt as if something was tugging at his lower left leg near the ankle when he ran.
The current diagnosis does not call for surgery, just more rehab and a different routine.
Luck did participate in individual work and some seven-on-seven drills during the first week of camp, but has been limited to working on his own and running walkthroughs since July 29.
Without Luck, Jacoby Brissett has been working with a starting offence that has struggled. Indy's defence has outplayed the offence consistently at camp and in Thursday's loss at Buffalo, the Colts generated only two first downs on their first seven series.
The Cleveland Browns will be in town Wednesday and Thursday for joint practices with the Colts. Reich had already said Luck wouldn't practice or play in Saturday's game.
"Coming into it, we were going to limit his playing time in the preseason anyway," Ballard said. "So right now, I'm telling you, most likely, he doesn't play in the preseason."
Luck's long absence and the uncertainty of what the injury was produced growing speculation among fans that there was a more serious injury and it was starting to sound like 2017 when Luck missed the entire season after having surgery on his throwing shoulder.
Ballard shrugged off any such notion.
Luck returned last season and led the Colts to their first playoff appearance in four years, won the league's Comeback Player of the Year award and went to his fourth Pro Bowl.
"Look, this is not 2017," Ballard said. "When I came in the door, one of the things we talked about was building a team and it wasn't all going to be about one guy. I understand the importance of Andrew Luck. Look, he's a top-five quarterback in the league, but we have another guy we like (Brissett). So we'll treat it and we'll move forward and we'll deal with whatever we have to deal with going forward."
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