Rex Grossman (8), center, became the first Redskins quarterback to throw for more than 300 yards in three of his first four starts since Sonny Jurgensen in 1969. (John McDonnell/THE WASHINGTON POST)

In the wake of his season-opening performance, Washington Redskins quarterback Rex Grossman made the media rounds last week, hopping on “SportsCenter,” the NFL Network and “Pardon the Interruption,” among others. Everyone wanted to talk about the quarterback’s big game.

But Grossman had won games before, he’d put up big numbers and had strung together four solid quarters. The tougher task comes Sunday when the Redskins learn whether Grossman can follow it up with another strong outing.

He set a high bar in last Sunday’s win over the New York Giants by throwing for 305 yards, completing 61.8 percent of his passes and posting a passer rating of 110.5. Only twice in his career has Grossman managed a quarterback rating of at least 100 in consecutive weeks, both during the 2006 season. And only once has he managed a completion percentage of at least 60 percent in consecutive games: the first two games of that same season. Can Grossman put up such strong numbers week in and week out for the Redskins?

“That’s the test for everybody,” offensive coordinator Kyle Shanahan said.

For Grossman, however, it’s more pronounced. Inconsistency has plagued him and is largely why he has spent the past 31 / 2 seasons holding a clipboard on the sideline in the NFL. But at Redskins Park, that doesn’t seem to be a big worry entering Sunday’s game against the Arizona Cardinals. For starters, Grossman says he has never before felt this comfortable in an offense.

“I just think I’m in a real good spot right now from my experience level and the offense that I’m in and personnel around me,” Grossman said. “I feel good about it. I’m going to make mistakes. Mistakes happen. But to be a quarterback and not be confused and not trying to, ‘What do I do now?’ — that’s when bad things happen. I don’t feel that very much.”

In fact, coaches say Grossman has been a model of consistency since he joined the team prior to the 2010 season. Even though Grossman has just four starts for Mike Shanahan, the Redskins’ head coach says he feels he knows what to expect from his starting quarterback with each outing.

“You kind of judge a quarterback based on what he does every day,” Mike Shanahan said. “I’ve been around him now for a year and a half or whatever it’s been. He always plays with that type of confidence, that type of mind-set. . . . How a quarterback gains trust is by the way he performs in practice every day. So you get a good feeling of any player by what he’s doing consistently in practice.”

Of course, coaches also like what they’ve seen from Grossman in game situations. The Redskins knew he was capable of throwing a deep ball, of hitting a guy on a slant or dumping off the ball when he senses a blitz. But they were pleased with how he bounced back from some of his bad plays last Sunday.

Grossman began the game 0-for-4 passing in two stalled drives. His confidence never wavered, though. He had a couple of bad possessions in the second half. Early in the fourth quarter, Grossman was sacked for a 14-yard loss and fumbled the ball. It’s the exact kind of play that lost Grossman his starting job four years ago in Chicago.

“In the NFL, people are going to have bad plays,” Kyle Shanahan said. “It’s all about how you respond.”

On Washington’s next possession, Grossman clearly wasn’t rattled, leading the offense on a 70-yard scoring drive. The quarterback was 5-of-6 passing for 53 yards on the drive, which was capped by a four-yard touchdown pass to Jabar Gaffney.

“I think I’m just smarter about it because of the offense,” he said. “The offense allows me to do the things that I like to do without trying to manufacture them myself.”

In all, Kyle Shanahan estimates that Grossman misplayed only five snaps in the season opener. Grossman has now topped 300 yards three times in his four starts for Washington, the first Redskins quarterback to do so since Sonny Jurgensen in 1969.

The stage could be set for another big statistical game this weekend. Last Sunday the Cardinals allowed Carolina rookie Cam Newton to throw for 422 yards in his first professional game. While Arizona has a strong blitz attack, the secondary was suspect in the Cardinals’ season-opening win over the Panthers.

“Obviously, we didn’t play our coverages very well,” Arizona Coach Ken Whisenhunt said. “It was not a very good outing for our defense in the first game so we have a lot of work to do. Our guys are focusing on trying to correct that this week. We’re going against a good offense. I have great respect for Coach Mike Shanahan and what he does offensively.”