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The San Francisco 49ers and Washington Redskins are in do-or-die mode, and there are some role players on both sides who must play at the top of their games to ensure victory on Monday Night Football.

San Francisco enters the contest on the outside of the NFC playoff picture, currently in seventh place behind the Arizona Cardinals. The 49ers lost two games in a row heading into this game, and a third straight loss would be a crippling blow to the team's Super Bowl aspirations.

Washington is in even worse shape, though it's not completely out of the playoff hunt just yet. With a record of 3-7, this team is just two games behind the Philadelphia Eagles and Dallas Cowboys for the NFC East lead.

But one more loss would be the final nail in Washington's coffin this season, while a victory would keep the team's slim playoff hopes alive for at least one more week.

Needless to say, a lot is riding on this contest.

With that in mind, here's a look at a couple of X-factors who must show up big for their respective teams on Monday.

Mario Manningham, WR, San Francisco

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San Francisco's passing offense has been nonexistent lately, and the 49ers rank dead-last in passing offense this season.

The battle cry from 49ers fans all year long has been, "Wait until the 49ers get healthy at the receiver position, then you'll see just how good this offense can be."

Unfortunately, to this point in the season we've yet to see this theory come to life.

Michael Crabtree is still not ready to play, but Mario Manningham has already come back from his knee injury. He only has four catches for 38 yards in his first two games back, though, and the 49ers desperately need more production from him going forward.

Logan Paulsen, TE, Washington

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Rookie tight end Jordan Reed isn't going to suit up for Monday's game after suffering a concussion last weekend, as noted by Mark Maske of the Washington Post:

Reed has been one of the few bright spots for Washington this year, catching 45 passes for 499 yards and three touchdowns. That kind of production is difficult to replace, and the man responsible for this job on Monday will be Logan Paulsen.

Paulsen has been mainly utilized as the team's blocking tight end this season. He's caught just 13 passes for 122 yards and one touchdown, but he'll need to come up big for Washington in this upcoming game in order to open up the field for the team's receivers outside.

Glenn Dorsey, DT, San Francisco

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If Washington has any chance of winning this game, it'll need a strong showing from Alfred Morris.

The 49ers feature one of the league's top pass defenses, allowing just 220 yards per game, but San Francisco has been exploited on the ground at times, allowing 103.8 yards on average and nine total rushing touchdowns.

The Redskins bring the league's No. 1-ranked rush offense into this game, averaging 155.2 yards per game, and Washington has scored 12 rushing touchdowns.

Glenn Dorsey is more of a pass-rushing defensive tackle than a run-stuffer, but injuries have forced him into the starting lineup. If the 49ers have any chance of shutting down Washington's potent rushing attack, however, he must play better than he's played all year long.

Brandon Meriweather, S, Washington

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The 49ers like to run a lot of misdirection plays on offense to try and get opposing defenses off-balance. When it works, big plays open up in the passing game, most often involving tight end Vernon Davis, who has caught eight of the 11 touchdown passes thrown by Colin Kaepernick this year.

The reason it's so effective is that the 49ers feature a powerful rushing attack, which the hard-hitting Brandon Meriweather will be eager to attack. Meriweather is prone to getting fooled, though, and if he bites on a fake or two, then the 49ers will suddenly be ahead by a couple of scores.

Though the 49ers don't feature anyone other than Davis who can legitimately stretch the field, Meriweather needs to play with extreme discipline on Monday night or suffer embarrassment at the hands of Kaepernick.

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