Marcus Rush, Garrison Smith making their case for roster spots

SANTA CLARA, Calif. -- The San Francisco 49ers beat the Denver Broncos 31-24 in their second preseason game on Saturday night. Here's a few leftover notes and observations from that game:

* 49ers coach Chip Kelly practices what he preaches when it comes to pushing competition at all positions. Many coaches talk about having an open mind with regard to positional and roster battles but don't actually follow through. But Kelly takes it serious, which is why it's worth noting when previously-under-the-radar players make an impact in a game. On Saturday night, there were two who stood out live and again when watching the tape: outside linebacker Marcus Rush and defensive lineman Garrison Smith, both of whom spent last season on the practice squad.

Rush was a no-brainer since he posted three sacks and forced a fumble. But he was consistently disruptive and didn't just fall into those sacks. Most of his success came on speed rushes, but he also showed an ability to convert speed to power and disengage blockers rather than simply run around them. Kelly said after the game that Rush knows he must make his mark on special teams in order to nail down a roster spot but this game had to open some eyes even if much of his production came against backups.

Smith also had a solid stat line but his work was perhaps most impressive for how he was able to make a difference in multiple ways. With Glenn Dorsey, Arik Armstead and DeForest Buckner sitting out, Smith got reps with the starters and played 39 snaps, recording five tackles, including two for loss, a sack and a quarterback hit. Defensive coordinator Jim O'Neil has proved unafraid to move his defensive linemen around, and Smith did some of that in this game. In addition to the stats above, Smith also showed a knack for being hard to move in the run game and taking on multiple blockers to allow his linebackers to flow to the ball.

"I thought Garrison played an outstanding game," Kelly said. "I think between him and Marcus, if you picked two standouts, and I thought there was a lot of other standouts, but those two really from a production standpoint kind of jumped off when you watch the tape, when you got a chance, you’re flying home last night, just watching the tape. The two of those guys were around the football a lot and causing a lot of disruption in Denver’s offense. So both those guys had really, really good games in Week 2.”

Neither Smith nor Rush had registered on many roster projections, but another strong performance or two like Saturday and that could easily change.

* Anthony Davis was serious when he said he offered to move to guard because right tackle Trent Brown is playing like one of the team's five best linemen. Brown showed in practice last week that he could hold his own against a top pass-rusher like Denver's Von Miller and then was again solid in the game. He also was moving people in the run game (see Carlos Hyde's touchdown run for proof of that). On tape, Brown looks the part of a player who trusts his technique and is reacting more than thinking when a pass-rusher tries something different.

* Like Smith, rookie defensive lineman Ronald Blair got plenty of work in the absence of some of the other key linemen. He played 51 snaps, second most among 49ers defenders. Blair has been used all over the defense in the preseason, and this game was no different. A lot of the discussion about Blair has focused on his pass rush -- and rightfully so -- but Blair looked stout setting the edge in the run game and genuinely looks like the type of movable chess piece that O'Neil won't hesitate to use a lot in 2016.

* Cornerback Chris Davis got another turn as the team's nickelback (he actually started, as the 49ers began in sub-package) and again fared pretty well. He allowed an early completion but also had a pair of pass breakups and continues to show a good sense for where the sticks are in relation to the ball.

* Running back Mike Davis wasn't able to follow his strong first preseason outing with another. His two fumbles will drive Kelly and the 49ers nuts. In fact, the turnovers as a whole must stop. The official scoring in the first game credited one fumble to quarterback Thad Lewis, but a running back has been at least tangentially involved with all five of the Niners' giveaways in the first two games. It's a safe bet that ball security will be a point of emphasis this week.

* I'd be remiss not to mention the early returns the 49ers are getting from their revamped offensive line. It was weakness last year, and though it's only the preseason, this looks like a better, deeper group that genuinely can excel in 2016. Through two games, the 49ers are second in the NFL in yards per game (404.5), first in rushing yards per game (210) and tied for fifth in sacks allowed per pass attempt. What the starting five looks like on opening night is still up for debate, but not because nobody deserves a couple spots. It's actually the opposite, which is a good thing for the Niners.

* Aside from the fumbles, the other thing that still has to be a concern on offense is the lack of an emerging threat at wideout. The Niners have been hit by injuries in the receiver group, but unlike guys like Rush and Smith, nobody is stepping up to stake a claim to a job given those opportunities.

* Kelly said there won't be a hard and fast plan for starters playing time Friday against Green Bay, but the general plan is to play the starters a bit more.