Right tackle Bobby Massie (70) clears some space for running back Andre Ellington Sunday.

Bobby Massie watched the video from Sunday's game – the first game of the season in which the right tackle actually got to play right tackle – and was pleased.

Twenty-one snaps Massie got in, and he had just one mental error.

"What'd I show?" Massie said. "I showed I can play. It was a big thing because I had a lot of mental errors in camp and I eliminated that."

A lot isn't an exaggeration, either. Once, Massie was going to battle veteran Eric Winston for the starting job, but that dissolved into a sea of

training camp mistakes. Massie said he had more than 40 mental errors in camp, a huge number that clarifies why the second-year tackle couldn't get on the field after closing his rookie season strong.

"It was just learning the offense," offensive coordinator/offensive line coach Harold Goodwin said. "He did have quite a few (mental errors). The biggest thing I told Bobby is, 'You've got to cut them down.' Obviously when you put a guy on the field like that you have to be able to trust him. He's earning that trust again with me."

Massie joined starting left tackle Bradley Sowell as the young players getting some time on the offensive line. Rookie guard Earl Watford doesn't sound like he's close to being the third, however, after Goodwin said Watford is taking "baby steps" in his development.

At right tackle, Winston remains the starter. Coach Bruce Arians said he'd like to continue to get Massie some work going forward, but it will depend on injuries whether the Cards can even afford to have Massie active (he and Winston both only play right tackle, unless it was a drastic emergency.)

 Massie thinks his play has earned more time. "But it's not up to me," he said.

BETTER ELLINGTON?

Rookie running back Andre Ellington had a career-high (thus far) 154 yards rushing on 15 carries Sunday, but acknowledged, "I left a few yards out there."

"There are some of those plays, you wish you could get back," Ellington said. "That's what the next game is for."

Arians said he'd like to increase Ellington's touches, although that might come through pass receptions to get Ellington in space. Goodwin said he personally thinks Ellington is smart enough to be able to handle a lot of carries, but reiterated he doesn't want Ellington to get beat up.

In the meantime, Ellington wants to pick up as many yards as he can when he does get the ball.

"You are never going to have a perfect game," Ellington said. "It's hard to be perfect. But you can be close to it."

GOODWIN GOES "SO-SO" WITH OFFENSE

Goodwin described the Cardinals' offense as "so-so" after the first half of the season, not a surprise given the fits and starts of a unit that had higher expectations coming in. The running game needs to stay productive, Goodwin said, and as usual, he brought up better pass protection and overall line play.

"There is still a lot of room for improvement," Goodwin said. "You can see the potential. There are a lot of times our offense gets going and something happens and we start to sputter. When it's on, it's on. We have to make sure it stays on."