SANTA CLARA Two-thirds of the players on the 49ers' roster head into tonight's exhibition finale against the Chargers hoping to exit it quickly and without an injury.
The other third will enter remembering the words of Scott Tolzien.
Tolzien is the locker-room poster boy for the importance of the fourth preseason affair. He was an undersize and undrafted quarterback for San Diego at this time last season, and the Chargers planned to place him on their practice squad.
But when Tolzien had a great game against the 49ers in the finale 16 of 23 for 226 yards, a touchdown and an interception his prospects changed. The Chargers had to waive him in order to get him on the practice squad, and when they did, the 49ers pounced and placed him on their 53-man roster.
The difference was significant in terms of salary and stature.
Tolzien shared that story with a group of backup offensive linemen and wide receivers this week. The lesson is that while a great game may not improve their prospects on their current squad, there are 31 other teams that will be scouring game film afterward.
"He told me that game was a big game for him because it basically got him a roster spot here," said Nathan Palmer, an undrafted receiver from Northern Illinois. "Having that film out there is really important for young guys like myself."
Tolzien, meanwhile, again is fighting for a spot on the roster. He and Josh Johnson have been splitting snaps all summer including in preseason games as they compete to be the 49ers' No. 3 quarterback.
Tolzien is eligible for the practice squad. Johnson is not. But placing Tolzien on the eight-man squad means the 49ers risk losing him the way the Chargers did a year ago.
Tolzien and Johnson figure to play more today than they have in the first three games as the 49ers look to preserve their starters. Still, that doesn't add up to a lot of plays when there are four quarterbacks on the roster, and Tolzien acknowledged that there is pressure to make eye-popping plays.
He said the trick is to relax and look to make completions.
"If they're there, take them," he said of big plays. "But at the same time, make sure they're calculated risks."
Other backup roles also are undecided.
Defensive coordinator Vic Fangio this week said that both rookie safety Trenton Robinson and newcomer Darcel McBath took a step forward Sunday in Denver. They and undrafted rookie Michael Thomas are competing to be the 49ers' fourth safety.
An injury to Demarcus Dobbs muddies the bottom of the roster. Dobbs, who was on crutches this week, figured to be both a backup at tight end and defensive end.
His injury could open up a spot at one or both of those positions. But other positions would have to yield a roster spot as a result. The 49ers must cut 22 players Friday to reach the 53-man roster limit. They can begin to build their practice squad Saturday.
An initial round of cuts occurred Monday, and Palmer said it was a decidedly unpleasant day.
"And any time that you don't know, there's some kind of fear there," he said. "So my phone rang, my heart would drop. The phone buzzed, my heart would drop. If anybody called my name it didn't matter who my eyes got big. It was like, 'This could be it.' "