Credit: Christopher Hanewinckel-US PRESSWIRE

In the preseason finale, the 49ers go up against the Chargers in what will be the final chance for bubble players to make their cases for the regular season roster.  This will be the 40^th exhibition game the 49ers have faced the Chargers and the 26^th straight year the teams have met in the preseason.  The all-time preseason series is tied at 20-20.  The first-team units for San Francisco and San Diego will probably not see any action, and if they do it will only be for one or two series.  With the final roster cuts coming on Friday, the game will still have excitement, as bubble player’s fight for the last roster spots.  Here are four bubble players to watch out for:

San Diego Chargers (3-0) vs. San Francisco 49ers (2-1)

Candlestick Park

Thursday, August 30 * 7:00 p.m. (PDT)

Anthony Dixon

At the start of training camp, it looked as if Dixon would not make the regular season with four other running backs on the roster ahead of him.  Sensing he could find himself cut from the team, Dixon asked to try out at fullback, which Jim Harbaugh allowed.  Entering the preseason finale and coming off carrying the ball 13 times for 58 yards and a 26-yard touchdown this past weekend, Dixon is looking like he might make the final roster, at running back.  A lot will depend on how he plays against the Chargers.

Rock Cartwright

Cartwright and Dixon are basically fighting for the same roster spot.  Cartwright is a running back but the 49ers would use him mainly on special teams, where he excels, should he make the roster.  The deciding factor could be special teams coach Brad Seely who could make the case for Cartwright over Dixon.

Perrish Cox

After sitting out all of last season fighting sexual assault allegations, which he was cleared for, Cox finds himself this season fighting for a roster spot on the 49ers.  With his great play this preseason, including two interceptions, he appears to be a lock for the regular season roster.  What is unclear is where he will be on the depth chart.  Will he be the No. 4 or No. 5 cornerback?  Tramaine Brock is currently the No. 4 cornerback, but he struggled in the preseason, while Cox has played well.  Cox needs to get better at tackling but he looks as if he has played is his way back into the NFL and onto the 49ers regular season roster.

Scott Tolzien

With Alex Smith as the starter and Colin Kaepernick the main backup, the question is should the 49ers keep Tolzien or Josh Johnson, or both?  Tolzien has an edge because he was the third-string QB last season, is familiar with the offense and has played better than Johnson in the exhibition games.  One edge Johnson has over Tolzien is he was Harbaugh’s quarterback while both were at the University of San Diego.  Harbaugh is loyal but I don’t think he will keep four quarterbacks on the roster.  Tolzien is eligible for the practice squad.  But he would likely be picked up by another team because the 49ers would have to place him on waivers before adding him on the practice squad.