ENGLEWOOD, Colo. (AP) — Drew Lock says he's not sure when his sprained right thumb will allow him to throw a football again and Broncos coach Vic Fangio won't rule out placing the rookie QB on injured reserve to start the season.
Lock jammed his thumb when he was chased from the pocket and tripped up by safety Marcel Harris in Denver's preseason loss to the 49ers on Monday night.
Although X-rays were negative, Lock was diagnosed the next day with a serious sprain that will force him to miss the rest of the preseason and might even sideline him into the regular season.
Fangio called it "a pretty serious injury for a quarterback," adding that the team's not sure of a timetable for his return and that IR was a possibility "if we don't think he could play for a while."
The night he was hurt Lock said it was a "little sprain," like he'd had "playing basketball 1,000 times."
"I'm not 100% sure," he said, adding he was "just going to leave that up to those people in that (trainers) room to kind of evaluate it a little bit. I know my pain tolerance. I know that level of stuff. But I think they're going to make the best decision on when I should be stepping back out on the football field."
With Lock sidelined and starting QB Joe Flacco sitting out Saturday night against the Rams along with most of the other starters, Kevin Hogan will get the start and rookie Brett Rypien will made his NFL debut in relief, Fangio said.
Lock, a second-round pick out of Missouri, was making a move to leapfrog Hogan and secure the backup QB job when he got hurt.
"I felt as if I was starting to play a little better and maybe earn that role," said Lock, who succeeded Flacco on Monday night and was 7 for 12 for 40 yards against San Francisco.
"He was improving and I saw some good strides," Fangio said. "I'd say he was tracking toward that. I wouldn't say he had it yet."
Lock's injury complicates plans for him to serve as Flacco's understudy and could have a ripple effect on the rest of the roster. The Broncos already have two injured players on offense, fullback Andy Janovich and running back Theo Riddick, whose timetables don't make them good candidates for IR.
Fangio said the tough thing about a thumb injury for a QB is that he can't do much work while he's out, although Lock vowed to double down on his mental preparation and said the Broncos' virtual reality system that allows him to get a first-person view of every other QB's snaps "is going to be heavily used."
One thing he won't change, Luck said, is his scrambling style.
"I feel like that's what got me here," Lock said as linebacker Von Miller nodded in approval nearby. "So, stopping that at any time now because I had just this little kind of a freak injury happen, that's just not who I'm going to be as a quarterback."
The Broncos aren't looking just yet for another veteran QB. Hogan was Case Keenum's backup in Denver last season and Fangio has been pleased with his steady play this summer.
"He's a smart guy, he can run the offense," Fangio said. "He's always been one of those guys that seems to make a play when there isn't one there — like the scramble he had the other night for a touchdown. So, he's got some playmaking and some improvisation in his game."
Notes: Miller presented Fangio with a cake and a trademark gray sweatshirt for his 61st birthday Thursday morning. Miller said he didn't have to take up a collection because players get the sweatshirts for free: "It's the thought that counts with him. I don't think it matters how much it costs. And free is probably better with Coach Fangio."
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