The San Francisco 49ers are set to take on the San Diego Chargers on Thursday in each team's final preseason game. It's week four, which means we're not going to see many starters, but there are plenty of younger players and aging veterans vying for roster spots and backup roles.

On Saturday, teams will have to cut 22 more players to get down to the 53-man roster limit. This final preseason game may not be filled with action from start to finish, but it's incredibly important to the coaches and players. Let's take a look at the teams involved.

Meet the Chargers

San Diego won their first preseason game last week, besting the Arizona Cardinals 24-7. The starters played a significant amount of time in that one, but they'll likely not get much time at all in this game. Some of the starting offensive linemen should be able to get some more time as they have three newcomers, including rookie D.J. Fluker.

The Chargers have some backup spots up for grabs, but more than anything, eyes are on the defensive side of the ball. The scheme they're implementing is a big change, and we might see a few starters on defense throughout the first quarter. They can finish the preseason with a 2-2 record if they win this one.

Meet the 49ers

The big story for the 49ers: the play of wide receiver Jon Baldwin. The 49ers traded A.J. Jenkins to the Kansas City Chiefs for Baldwin, and in his debut in Week 3, he made two catches. Jenkins couldn't manage even that with San Francisco. It's likely that Baldwin will see some significant snaps.

The 49ers need to figure out the wide receiver position due to injuries to Michael Crabtree and Mario Manningham. Anquan Boldin is the starter, so it's unlikely that he'll see much time, but he also doesn't need it. Nor does tight end Vernon Davis, who will probably be the No. 2 receiving option.

Local Takes: Chargers

John Gennaro of Bolts From The Blue believes that Robert Meachum is a player to watch in the fourth quarter since he's fighting for his job:

Meachem needs an outstanding game, with at least one touchdown (or possibly an injury to another wide receiver that sits above him on the depth chart), for Chargers GM Tom Telesco to let him stay in San Diego this season.

Local Takes: 49ers

David Fucillo of Niners Nation points out that rookie Eric Reid has been named the starting free safety, which probably means he won't play long on Thusday:

In case there were any questions about who was starting at free safety, Vic Fangio answered them convincingly. During his press conference today, Fangio was asked if Eric Reid would be the starting free safety this season, and Fangio confirmed he would be the starting free safety when the regular season begins.

Odds

The 49ers opened as three-point favorites, though the line has moved to even money on most sites, according to Odds Shark.

Next Week

The 49ers begin their regular season against the Green Bay Packers. The Chargers open against the Houston Texans.

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