Three things to watch:
1. The "other" Brandon Marshall: It will be the first glimpse of the Broncos without linebacker Danny Trevathan in the lineup. Trevathan, who was the team's leading tackler in 2013, is expected to miss up to eight weeks as he recovers from a fracture at the top of his tibia in his left leg. Marshall has worked in Trevathan's weakside spot this week. Trevathan is difficult to replace because of the variety of roles he fills in the defense, playing in the base as well as all of the specialty packages in the nickel (five defensive backs) and dime (six) as well. Marshall worked in the base, the nickel and the dime in practice this week, showing good speed to the ball. Against the 49ers he will get to show whether he can hold up against a power offense that also likes to push the ball to the tight ends in the passing game.
2. Return policy: The Broncos are three weeks of practice into the preseason and don't appear much closer to choosing a punt returner or kickoff returner. So consider those jobs still open for a worthy candidate or two to step forward. The fallback choices are not the ones the Broncos would prefer -- Wes Welker returns punts, Emmanuel Sanders kickoffs -- given the injury potential. Welker had two concussions last season alone and Sanders had been limited for much of camp with a thigh injury. Keep an eye on Omar Bolden in the kickoffs return role and Jordan Norwood on punt returns. Rookie wide receiver Cody Latimer has also taken some kickoffs in practice, and the potential kickoff returners have all had some ball security issues at times in practice.
3. Work fast: With the starters set to gobble up the most playing time entering the third quarter of next week's game -- Aug. 23 against the Houston Texans -- this one will be a good opportunity to see those who have pushed themselves up a crowded depth chart get some quality work. Wide receiver Norwood continues to show an understanding of the team's offense and has consistently been in the right place at the right time with catch after catch. Juwan Thompson, as the biggest back on the roster, gives the offense something the other backs can't in the run game. He has also shown good hands as a receiver and even a little more speed carrying the ball than the Broncos may have expected. Also, undrafted rookie linebacker Shaquil Barrett got some snaps with the starting defense this week and figures to get a long look as well.