Three things: 49ers-Texans

Three things to watch for Saturday night in the San Francisco 49ers' second exhibition game, this one at Houston (8 p.m. ET):

1. Receiver mix. This game would seem to provide an opportunity for showcasing various combinations at wide receiver. The 49ers have suffered injuries at tight end. Delanie Walker is recovering from a knee injury. Nate Byham reached an injury settlement with the team after experiencing additional knee trouble. Having fewer front-line tight ends should leave more opportunities for wide receivers, at least in theory. And the 49ers do have renewed depth at wideout. I'll be watching to see if the connections Alex Smith made so frequently in practice this week -- to Mario Manningham, Randy Moss and, of course, tight end Vernon Davis -- carry over into the early stages of this game. It's also not yet clear which receiver will start opposite Michael Crabtree, and whether that other starter will be more than a rotational player.

2. Backup QB race. Colin Kaepernick has established himself as the likely No. 2 quarterback. That appears to be partly because veteran Josh Johnson hasn't done much to change the coaches' minds. Johnson and 2011 undrafted free agent Scott Tolzien could be fighting for the third job. The 49ers would seemingly want some experience behind Smith, but not simply for the sake of having experience. Johnson got only four pass attempts in the preseason opener. Tolzien got 13, completing 10 of them for 84 yards. He threw one interception. We should have a better feel for the backup situation coming out of this game.

3. Perrish's push. Perrish Cox, sidelined last season while facing sexual-assault charges (he was acquitted), is making a strong push for playing time as the nickel corner. He showed well on special teams and in the defense against Minnesota last week. Let's see how he and No. 1 nickel corner Chris Culliver perform. Update: With Seahawks-Broncos also on the mind, I initially projected Cox facing his former team. That happens next week, when the 49ers face Denver. My bad.