Who has something to prove this weekend?

John Beck is trying to hold off Rex Grossman in Washington, where Donovan McNabb was the starter a year ago. (AP)

Week 3 of the NFL preseason is traditionally when we get the best sign of what teams will look like come the regular season -- starters see extended minutes for the last time, generally, with preseason Week 4 devoted to guys fighting for roster spots.

Some teams are in better shape than others as we enter this week's slate of games. Wins and losses right now don't mean anything, but with the Sept. 8 opener between Green Bay and New Orleans approaching on the horizon, teams will want to take a step forward in their third preseason games.

And here are a handful teams with something to prove this week:

• Washington Redskins: They've been impressive in preseason wins over Pittsburgh and Indianapolis, which of course has rabid Redskins Nation dreaming of rainbows, puppy dogs and Super Bowls. Thursday night's matchup with the Ravens should give us a better indication about the validity of that fervor.

Specifically, it will put John Beck to the test. Beck, who's battling Rex Grossman to be Washington's No. 1 QB, picked apart the Colts to the tune of 14-for-17 passing for 140 yards. He was sacked three times, though, and Baltimore's aggressive defense will give him a stout test.

Likewise, the Ravens' offense will bring more to the table than a Steelers team that benched its starters very early and a Colts group without Peyton Manning.

• Seattle Seahawks: Pete Carroll actually gave his first-team offense a full half of work last week against Minnesota. It did not go well.

The Vikings ate the Seahawks' offensive line alive, sending Tarvaris Jackson scrambling for his life on more than one occasion. A visit to Denver Saturday will give Seattle another chance to pull it together.

There's enough talent on the Seattle offense to be intimidating this season -- Jackson, Marshawn Lynch, Sydney Rice, Zach Miller. None of that will matter if the Seahawks can't block.

• Jacksonville Jaguars: The Jags' preseason opener against New England was a nightmare, ending in a 47-12 loss. Jacksonville rebounded nicely on defense last week, holding Matt Ryan and the explosive Atlanta offense to 10 points in the first half, en route to a 15-13 win.

The defense should be able to repeat that performance at Buffalo Saturday -- failure to do so would be cause for some concern.

And there's already enough to worry about on offense, where incumbent starting QB David Garrard is trying to get healthy after a back injury and hold off rookie Blaine Gabbert. Both were out of sync against the Falcons, with Garrard finishing 7-of-12 for 99 yards and a pick, and Gabbert 11-of-23 for 96 yards. Someone needs to step up against the Bills.

• Dallas Cowboys: Back to the NFC East we go. Tony Romo, in spite of an egregious interception thrown into about sextuple coverage, turned in a decent performance against San Diego last week -- 8-of-12, 58 yards, one TD and that INT. His No. 1 running back, Felix Jones, has had two impressive preseason showings, too, so the Cowboys' offense should be good to go.

Can the same be said about the defense? San Diego scored touchdowns on two of its three possessions with the first-team offense on the field in Dallas, one week after Kyle Orton and the Broncos' O marched 74 yards for a field goal in its only series.

The Dallas defense, remember, is transitioning to life under new coordinator Rob Ryan. A coaching switch like that naturally leads to some adjustment period. The Cowboys are running out of time to make those fixes, though. They'll get another shot at Minnesota Saturday.

• New York Jets/New York Giants: These two get paired up because they're conveniently playing each other in the stadium they share. For both, last week's games were a success.

The Jets unleashed Plaxico Burress at wide receiver, and he showed an immediate rapport with Mark Sanchez. Not coincidentally, the Jets scored 17 first-half points against hapless Cincinnati, with Sanchez tossing two TDs, including one to Burress.

Meanwhile, the Giants destroyed the Bears 41-13. All three units came to play for New York, though the victory was marred a bit by the season-ending ACL injury Terrell Thomas suffered.

This week is important to the Big Apple's teams for different reasons. The Jets want to keep their offensive momentum headed in the right direction; the Giants need to keep plugging up injury holes and make sure they have enough viable pieces to compete come the regular season.

Carolina

Miami

Philadelphia

Houston

Denver