All signs may have pointed to John Beck through camp, but Mike Shanahan chooses nine-year veteran for opener against Giants. (Jonathan Newton/The Washington Post)

The rain had already started falling early in practice Monday when Mike Shanahan gathered his players together and ended the summer-long suspense surrounding the team’s starting quarterback position. Teammates began clapping when the Redskins’ coach anointed Rex Grossman the victor, naming the nine-year veteran as the starter for Sunday’s season opener against the New York Giants.

“Rex won it by an edge,” Shanahan told reporters later.

Shanahan said he met with both Grossman and John Beck over the weekend and wanted to share his decision with the team before players began preparations for the Giants. He praised both quarterbacks and said each was capable, but Shanahan also made clear he intends to use Grossman for the entirety of the season.

“As you’re evaluating everything on a day-to-day basis, you kind of get a gut,” Shanahan said. “If someone you think makes a little jump, you go in that direction. I said from Day 1, any time you got confidence in two quarterbacks, that’s pretty good in the National Football League. That’s what I have right now.”

Grossman and Beck were not made available to reporters Monday.

Grossman said following the team’s final preseason game last week he hoped he’d done enough to impress coaches.

“I was real happy with how I played this preseason in practice and in the games,” Grossman said. “I feel like I put my best foot forward, and I feel good about it.”

Grossman, 31, won the job over Beck, 30, the fifth-year player who Shanahan believes has superior athletic ability. But even as buzz built around Beck throughout a news-starved offseason and signs pointed to him as Shanahan’s preferred starter, the coach pledged to hold an open competition and each quarterback made three preseason appearances.

Grossman was 34 of 53 passing for 407 yards, two touchdowns, one interception and had a passer rating of 92.3. In Beck’s three games, he was 30-of-48 passing for 356 yards, one touchdown, two interceptions and a passer rating of 74.7.

“John played well — so well to the point that you almost want to give it to him,” said wide receiver Santana Moss. “But when you’re going into a year when you’re trying to win now, you’re trying to do some things, you want to be solid at the QB position. Given that Rex had one more year in this offense than John, it was only right.”

Having served as the Houston Texans’ backup in 2009, Grossman has two full years playing in offensive coordinator Kyle Shanahan’s system. Even last year, after the Redskins acquired Donovan McNabb in a trade with Philadelphia, Grossman was the quarterback on the practice field who had the best grasp of the offense.

“Last year when he came here, we didn’t know what to expect. We had McNabb so we weren’t really keying on Rex being the guy,” Moss said. “But when you watched him in practice, it was like, this guy is killing it out here.”

Grossman replaced McNabb as the starter with three games remaining in the 2010 season, his first starts since 2008 with the Chicago Bears. He completed 74 of 133 passes for 884 yards with seven touchdowns and four interceptions. His quarterback rating was 81.2. He looked even better and more consistent this preseason.

“He’s familiar with the system,” Shanahan said. “I thought he was pretty automatic with a lot of his reads. Hopefully, he plays accordingly.”

Grossman has 44 starts under his belt and led the Bears to an appearance in Super Bowl XLI. But he hasn’t been a regular NFL starter since 2007. That season also marks the last time Grossman started a season opener.

Grossman has been criticized for his lack of mobility and poor decision-making. But his teammates don’t seem to be lacking in confidence in him.

“Funny thing about it, I don’t think it’s his physical abilities,” said running back Tim Hightower. “Not that he doesn’t have it, but it’s really his demeanor, on and off the field, in the locker room — guys love him. You’ve got a guy at your leadership position and guys respond well to him, they gravitate to him and want to be around him. And you’ve got a chance to win.”

Coaches evaluated Grossman and Beck daily. They dissected their preseason games and studied film of the team’s daily practices. The two quarterback split reps with the first-team offense throughout the preseason.

Coaches said heading into the team’s final preseason game last week against Tampa Bay that the competition was still tight and no clear winner had emerged. If the decision really came down to the wire, then Beck’s last outing was the most damaging.

Because Beck had missed the preseason opener, coaches allowed him to start Thursday against the Bucs. Beck was 10 of 21 passing for 108 yards. He had no touchdowns, one interception and a rating of 43.4. Grossman did not appear in the game.

Though the quarterback competition is now over, Shanahan said he felt the preseason readied both his quarterbacks. Coaches and players said they’d feel comfortable with Beck in the pocket, too.

“You don’t really take a step back if we had to make a switch at quarterback for some reason,” Armstrong said. “Whenever you kind of got a 1a and 1b, it’s a good situation to be in.”