The Eagles selected McCoy in the second round of April's draft to back up Westbrook, who has been their star runner for the better part of this decade. In McCoy's first start, a 34-14 victory over the Kansas City Chiefs on Sept. 27, he rushed for 84 yards and a touchdown as Westbrook sat out with an injury.
"We have a lot of different personnel packages we can use," Mornhinweg said. "With both of them on the field, the things you can do are really endless."
In his first extended action against the Chiefs -- McCoy had 14 carries for 62 yards in the first two games -- the rookie showed excellent vision and a shifty running style. His speed was never a question.
"I thought I did well," McCoy said. "Could I do some things better? Sure I could. I picked up the blitz all right, but I could do it better. I can run crisper routes. But I thought overall I did OK. I was happy."
He'll be just as happy being on the field with Westbrook.
"That would be great," McCoy said. "I think it would definitely be a good thing. I'm sure the defense would pay more attention to Brian, and maybe I can sneak up in there and do some things. It would be cool.
"Hey, Brian is the starter. I'm still the backup. But if I can get some carries to make it easier on him, keep him fresh, that would be great."
Even when the running backs aren't on the field together, Mornhinweg anticipates using McCoy more as the season progresses. The days of teams having just one premier back are over.
"It's been over for a while," Mornhinweg said. "Our game has become so specialized. A lot of teams use a normal back, a third-down back, a change-of-pace guy. The one big back, it's been over, with a few exceptions -- those rare, special players -- and Brian was one of them."
Copyright 2009 by The Associated Press