Donovan McNabb has played all 16 games in a regular season only once in the last six years. For all his hard work to stay fit, there always seems to be something that causes him to miss a game. Or two. Or more.

That makes the battle for the Washington Redskins' backup job more than just a curiosity. Odds are someone other than the six-time Pro Bowl quarterback will be taking more than just a few token, mop-up snaps this season.

The latest name added to the mix is John Beck, a former BYU standout and second-round draft pick by the Miami Dolphins. Beck took part in his first Redskins practice Tuesday, a day after he was acquired in a trade with the Baltimore Ravens.

"It was definitely kind of weird playing with one team in the morning and then meeting with another team at night," Beck said. "The offenses are very different, so I kind of feel like a rookie coming in. Your head's spinning a little bit."

It sure looked that way. Beck was well off target with his first two throws in a 7-on-7 drill, including an awkward flat-footed attempt that certainly won't find a place in the Beck family archives. It took an easy screen toss to running back Ryan Torain to get the new guy with the red hair somewhat on track.

Beck wasn't alone, though. It was the first 7-on-7 of training camp, and it was a rough one. McNabb's first throw was a simple pass in the flat — right into the hands of cornerback Carlos Rogers for an interception. Rex Grossman and Richard Bartel didn't exactly light up the field, either.

"Usually it's this time of year when you're installing your offense and installing your defense that there are a bunch of lulls," coach Mike Shanahan said. "You have to push through it."

Grossman. Bartel. Beck. Shanahan had a history of keeping only two quarterbacks during his long tenure with the Denver Broncos, so there could be room for only one among those three behind McNabb on the 53-man opening day roster.

Gone from the competition is Colt Brennan, the Redskins' 2008 sixth-round pick who developed an incredibly persistent cult following — the Cult of Colt — after going 9 for 10 against backups in a preseason game as a rookie. But Brennan never appeared in a regular season game, spent last season on injured reserve after hip surgery and struggled mightily at this year's training camp. He was cut Monday after the trade for Beck.

Grossman has the decided advantage, having spent last year with the Houston Texans running this same offense under new Redskins offensive coordinator Kyle Shanahan. When McNabb has a question about the offense, he'll ask Grossman if the coaches aren't around.

Grossman also took the Chicago Bears to the Super Bowl at the end of the 2006 season, but that's also the one and only season he's kept a starting job from beginning to end. He's become one of those familiar, face-on-the-sideline veteran backups, throwing just 71 passes over the last two years.

Bartel is one of those young backups piling up time on the bench. He's been released four times in his NFL career and served as the Redskins' No. 3 quarterback for the final six games of last season. The trade for Beck has put him on notice.

"Sure, absolutely — that's kind of the way I take it," Bartel said. "I feel like to stay motivated, you put yourself in the situation, 'OK, new guy coming in, is this something about me?'"

Beck got into five games with the dreadful 1-15 Dolphins as a rookie in 2007 and might be best remembered for an infamous play in which the ball slipped out of his hands and flipped into the air while he attempted a pass against Buffalo. The Bills caught it and returned it for a touchdown, and Beck hasn't started a game since.

Beck spent last year with Baltimore and became expendable when the Ravens signed Marc Bulger to be their backup.

"That was a tough spot, those years back in Miami," Beck said. "But I was able to learn a lot. I didn't look back at that with any frustration. I had the opportunity to play in five games as a rookie, and that experience can help whenever my next opportunity comes."

The No. 2 job is Grossman's to lose, and the preseason games will give an idea what kind of drop-off can be expected if McNabb is out for any extended period of time this year.

"We really don't care what you've done in the past," Mike Shanahan said. "We want to see what you do out there on the practice field, how you play in these preseason games."

Notes: WR Malcolm Kelly (hamstring) remains at least a couple of days from returning to practice, dropping him further behind in his quest for a starting job. ... Remarkably, six days of training camp have yet to produce a single injury that has caused a player to miss a practice. Kelly hurt his hamstring before camp began. ... TE Chris Cooley, suffering from a rare case of the drops during this camp, had another pass go off his hands at the end of practice. He then spiked his helmet so hard it rolled 20 yards downfield.