ENGLEWOOD, Colo. (AP) -- The Denver Broncos did everything to prepare rookie quarterback Drew Lock for his first NFL start.
They designed a game plan around his strengths, had him take most of the snaps with the starters all week, praised his progress, prepped him for production meetings and interviews and declared he'll be brought off injured reserve and suit up Sunday for the first time.
The one thing they didn't do was anoint him the starter.
''We haven't decided yet,'' coach Vic Fangio insisted when asked Friday who will be his starting quarterback Sunday when the Broncos (3-8) host the Los Angeles Chargers (4-7). ''But we're definitely going to activate Drew tomorrow and he'll be dressing on Sunday for sure.''
Why the delay?
''I just wanted a chance to go in and look at the tape more extensively,'' Fangio said, adding he'll make up his mind ''probably tomorrow.''
It would make little sense for Fangio not to start Lock after giving him three-quarters of the snaps at practice all week, leaving only about 30 snaps for Brandon Allen, hardly enough for a QB with all of three starts on his resume to get ready for another starting assignment.
Fangio said the decision would come down to Lock or Allen, leaving undrafted rookie Brett Rypien out of the mix. Rypien could be the odd man out when Lock is activated off injured reserve, although there are several other possibilities with so many players nicked up.
Allen went 1-2 after veteran Joe Flacco went on IR with a neck injury, beating Cleveland in his debut but losing at Minnesota and Buffalo, which own two of the top six scoring defenses in the league.
Lock would be the seventh starting quarterback for Denver since Peyton Manning retired in March 2016 after the Broncos won Super Bowl 50, joining Trevor Siemian, Paxton Lynch, Brock Osweiler, Case Keenum, Flacco and Allen.
The teams remaining on Denver's schedule aren't that strong defensively.
The Chargers rank 11th in scoring defense, but that game is at home, so Lock wouldn't have to deal with the noise on offense. He will have to face the din in games at Kansas City and Houston, but the Chiefs rank 19th and the Texans are 17th in scoring defense. The final two games are at home against Detroit (25th) and Oakland (26th).
Lock, a project passer from Missouri whom the Broncos selected in the second round of the NFL draft, started the season on IR after spraining his right thumb in the preseason.
He returned to practice Nov. 17, taking about 10 snaps per practice for the first two weeks before his workload was ramped up this week.
''I think he's made progress each and every day,'' Fangio said. ''When you go from getting 10 out of 42 reps to getting 32 out of 42 three days in a row you should get a little better, feel a little more comfortable. I think he has.''
Although he wouldn't say definitively who will be his QB, Fangio said cornerback Isaac Yiadom will start in place of scuffling Devontae Harris on Sunday, and he said both Von Miller and Alexander Johnson are 50-50 for Sunday with knee injuries.
If Miller can't go, it will snap a 95-game starting streak, including the playoffs. The last game he missed was Super Bowl 48 after suffering a knee injury in the next-to-last regular-season game in 2013.
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