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ENGLEWOOD, Colo. --** You've heard it from coaches, and now you'll hear it from this observer: preseason games matter more than practice in determining the roster and how the depth chart will look. It's one thing to flourish in training-camp practices against teammates, whose moves and tactics become so familiar, you begin to have a sixth sense for knowing what they'll do next. It's something else against a foe you haven't seen before, and under the heightened scrutiny of a sellout crowd and a television broadcast.
Even an elite team like the Broncos has questions to answer Thursday, and there'll be five I'll examine with particular interest.
1. Who starts at safety next to Rahim Moore?
Moore appears set at one spot, barring injury; he looks more comfortable now than at any point in his career, and is able to apply his experience to help set the defense before the snap. Mike Adams is listed as the other first-team safety, but Duke Ihenacho has received the bulk of the first-team snaps in recent practice. Ihenacho's aggression and ability to anticipate the development of run plays has allowed him to distinguish himself, and he's also made plenty of plays against the pass, including a touchdown-saving swat of a Peyton Manning pass to Duke Ihenacho during Tuesday's practice. But will he be able to anticipate what the 49ers do as well as he does Denver's offense? The answer to that may determine whether he has a legitimate chance to start or ends up providing depth once again.
2. How much progress has Brock Osweiler made?
This is the moment to which the second-year quarterback's entire offseason has built. All the progress he's made on the practice field — from his improved touch on deep passes to his ability to command an offense in the no-huddle to his more decisive thought process in the pocket — will be re-evaluated if he reverts to some of his rookie habits Thursday. The Broncos have confidence that if something happens to Manning, Osweiler can steer the ship effectively; against the 49ers, we'll begin learning if this is actually the case.
3. How will the Broncos keep Manning upright?
Injuries and shuffling along the offensive line make this a key concern, since all other matters from Thursday's game are secondary to players emerging without injuries — none more crucial than Manning. The 49ers' first-team pass rush isn't quite as potent as usual without Justin Smith, who will miss Thursday's game, but the presence of Aldon Smith sustains it as a lethal threat. Defusing Aldon Smith will be the primary task of the tackles — which may or may not include Orlando Franklin, depending on his recovery from a Monday hip injury. But another spot to watch will be the interior; the 49ers can generate some consistent pressure from inside, which will test center Manny Ramirez and guard Ryan Lilja.
4. Which unheralded players will emerge?
Wide receiver Lamaar Thomas and linebacker Lerentee McCray have been among the practice-field standouts of recent days. Thomas emerged in the wake of injuries to receivers Greg Orton and Quincy McDuffie and made several nice catches during the Monday and Tuesday sessions. McCray has been disruptive working from the outside linebacker slots against the run and pass. But the players who rise in the games are often the ones who slip through the cracks in practice; do well Thursday, and you might find more repetitions on your schedule Saturday.
5. Among young cornerbacks, who's in the lead?
With Dominique Rodgers-Cromartie out with a high ankle sprain and Tony Carter hobbling a bit, this could be the best opportunity for Omar Bolden, Kayvon Webster and the Broncos' other cornerbacks to show that they're worthy of playing time. Bolden and Webster have mid-round draft pedigrees, but their training-camp work has been up and down, depending on the day, the play and the receiver they face. Both could use an outstanding performance in San Francisco to bolster their cases for playing time beyond special teams.
