Through five games, Rex Grossman accounted for every one of the Washington Redskins’ turnovers — nine interceptions and two lost fumbles in all. But the franchise’s biggest turnover to date can be credited to Coach Mike Shanahan, who made the bold decision to change starting quarterbacks this week despite the team’s 3-2 record.

John Beck, who hasn’t started an NFL game since 2007, will replace Grossman and lead the offense Sunday against the Carolina Panthers. Beck is the third starting quarterback Shanahan has used in 22 games as Washington’s coach. For as long as Shanahan lets him, Beck will try to do what Grossman couldn’t. If he holds on to the ball, he’ll have a shot to hold on to the starting job.

“There’s always going to be mistakes made in the game, but you can’t constantly turn the football over,” Shanahan said. “And if you do, you’re going to lose your opportunity to lead the football team.”

Shanahan informed both quarterbacks of his decision earlier in the week, and during a drizzly practice session Wednesday, Beck led the first-team offense for the first time this season.

“I’m just going to go out there and do the very best that I can,” Beck said. “Ball security is a point every single week, because it’s very hard to win in the NFL if you turn the ball over. Now it’s on my shoulders to take care of the football and put our team in the best position to win.”

In the locker room, Redskins players seemed to support the move. While Grossman had a strong arm, Beck is more mobile, which might be important this weekend. The Redskins are without left tackle Trent Williams, who is out with a high ankle sprain, and left guard Kory Lichtensteiger, who was placed on injured reserve Wednesday.

“John does a good job of moving around with his feet,” right guard Chris Chester said.

Teammates had watched as Beck and Grossman battled throughout the preseason for the starting job. Though Grossman won it, Shanahan has always said the competition was close. The tipping point appeared to be Grossman’s four interceptions in last Sunday’s loss against Philadelphia.

“I think those guys are pretty much neck and neck,” running back Tim Hightower said. “They’re pretty close, as far as ability-wise. Two different kind of demeanors, but they’re both good quarterbacks.”

Changing quarterbacks with a winning record isn’t common in the NFL, but Shanahan has done it once before: The Denver Broncos had a 7-4 record in 2006 when Shanahan replaced Jake Plummer with rookie Jay Cutler. Redskins players say the early change this season sends a clear message to the entire locker room.

“When you make a quarterback change like that, there’s a standard that’s set,” Hightower said. “I think that sends a very loud message to the rest of the guys on offense that hey, get your stuff together. We need guys to step up and make plays. It’s not later. It’s now.”

While players mostly said the right things Wednesday, the team wasn’t in unanimous agreement with the change. Wide receiver Santana Moss reiterated that he felt Grossman shouldn’t be yanked after last Sunday's bad outing. Still, he likes what he’s seen from Beck.

“He’s a very talented quarterback who hasn’t really had his shot yet to prove who he can be in this league,” Moss said. “I think he had a shot and hasn’t really done anything since that shot, hasn’t really had a chance since then.”

A second-round draft pick by the Dolphins in 2007, Beck appeared in five games during his rookie season, starting four of them. He finished with a passer rating of 62.0, with no touchdowns and seven turnovers in his four starts. Beck believes his second stint as a starter will be different.

“The situation I stepped in as a rookie was a difficult one,” he said. “We were winless, the organization had been through a lot of struggles that year. We were already 0-9. This is still the beginning part and this team has a good feeling about it.”

The Dolphins released Beck in 2009, and he spent the next season as a backup to Joe Flacco in Baltimore. The Redskins traded for him during training camp last year, though he saw no action in 2010.

Beck was hardly overwhelming this preseason for Washington, and he enters Sunday's game as a 30-year-old with just a half-dozen games under his belt. Shanahan said he still believes Beck has a bright future.

“Doesn’t matter if you’re 30. . . . I’ve got a lot of confidence in John Beck because he does have that mobility. He’s got a strong arm,” Shanahan said, “I’m not going to put him in the Hall of Fame yet. But I really do believe that he’s got a lot of talent.”

Sunday’s loss to the Eagles marked Beck’s first NFL action since his rookie season. He was 8-of-15 passing for 117 yards. He ran for one touchdown and, perhaps most importantly, had no turnovers.

Grossman said Shanahan called him into the head coach’s office Tuesday and told him Beck would be the Redskins’ new starter. “I was frustrated,” Grossman said. “Not completely surprised, but disappointed that I wasn't able to come back off that game.”

Grossman acknowledged his poor play in Sunday’s loss to Philadelphia but said he feels he should remain the team’s quarterback because of his performance through the team’s first four games.

“I do think they were good performances,” he said. “The frustrating part about it is they should’ve been great.

“I had an opportunity to make it clear as day, and it wasn’t,” he continued.

Beck will make his first start against a struggling Carolina team that has won just once in six outings. Defensively, they haven’t wreaked havoc like some of the teams Grossman faced. The Panthers, in fact, have just five takeaways; only three teams (Pittsburgh, New Orleans and Miami) have fewer.

The Panthers must prepare for a quarterback without the benefit of much film. Carolina Coach Ron Rivera said his staff will look at footage from Beck’s rookie season and some of his preseason action.

“Truthfully, you really don’t prepare for the individual, as much as you prepare for what they do offensively,” he said.

While Grossman couldn’t hide his frustration with Shanahan’s decision Wednesday, Beck’s excitement was palpable. He hasn’t simply been waiting five weeks for this opportunity; he’s been waiting four years.

“Things change in a blink of an eye. You’ve always got to be ready,” Beck said. “I’m just trying to move forward with this opportunity, do the very best that I can.”

Staff writers Barry Svrluga and Mike Jones contributed to this report.