While Vick left the Patriots game with 6:01 left in the first quarter after taking a shot to the ribs from linebacker Jermaine Cunningham, McCoy emerged unharmed from his two-plus quarters of work against the Patriots. Finished with nine touches. Rushed for 30 yards on seven carries, including a 1-yard touchdown run, and caught two passes for 12 yards.
You'll probably see little of him in the Eagles' final two preseason games.
But what if he goes down at some point? What if somebody takes out his knee or he pulls a hamstring or suffers one of those ever-popular out-for-6-weeks high-ankle sprains? Can the Eagles survive?
The three running backs currently backing up McCoy - Dion Lewis, Bryce Brown and Chris Polk - all are talented, but inexperienced. Lewis is a second-year player who had just 24 touches as a rookie. Brown and Polk both are NFL newbies.
"I'm OK with who we have [behind McCoy]," Andy Reid said. "I think we have quality there. As long as they continue to progress. Bryce is probably the furthest away as far as pass protection. But he's working very hard at it, and he's a big physical kid."
The 5-9, 195-pound Lewis is expected to open the season as the No. 2 running back. Brown, a seventh-round pick in April, and Polk, an undrafted free agent, are battling for the No. 3 job.
Unless Reid and general manager Howie Roseman decide to go with four running backs on their 53-man roster and no fullback, either Brown or Polk probably will open the season on the practice squad, assuming they aren't signed by another team.
Reid has been saying since March that he wants to lighten McCoy's workload a bit this season. McCoy played an NFL-high 894 snaps last season. His 321 touches (rushing attempts and receptions) were the fourth-most in the league.
But before he can lighten McCoy's load, he must have faith in the guy he's sending in to replace him. Not so much as a runner, but as a pass protector. Lewis' struggles in learning to block and pick up blitzes last year were the biggest reasons he was on the field for just 42 snaps.
"I remember talking about Brian Westbrook this way and LeSean this way," Reid said. "I would tell you the same thing with these kids here; that they need work in that area. They need to get going.
"Dion is getting better. You can tell he's been here a year and has worked on it. He has a better understanding now than he did last year coming in. He's more willing to stick it up in there. He has a technique."
Reid and general manager Howie Roseman considered bringing in a veteran running back to back up McCoy. But they tried that last year and ended up with a guy - Ronnie Brown - whose tires were balder than Elmer Fudd.
Both Polk and Bryce Brown are considerably bigger than Lewis. Brown is 6-0 and 225 pounds, Polk 5-11 and 225. Brown, who had 27- and 17-yard runs Monday night against the Patriots, is an intriguing player. He's a big body with 4.4 speed and excellent hands. But he only played in nine college games, and blocking was completely foreign to him when the Eagles decided to take a flyer on him in the seventh round in April.
"It's difficult," Brown acknowledged. "For me, it's definitely the hardest part of this offense [to learn]. I've never done it before.
"It's just about getting the reps and seeing it and doing it over and over. Watching the film and being able to recognize [blitzes] better. The sooner you recognize it, the easier it becomes."
Polk had some experience at pass-protection and blitz pickup at the University of Washington, which played an offense similar to the one the Eagles run. In fact, he's shown enough blocking adeptness this summer that offensive coordinator Marty Mornhinweg acknowledged last week the possibility of using Polk as a fullback "has been discussed and thought of."
That said, there's a big difference between serving as a lead blocker for McCoy and protecting Vick from the myriad of blitzes teams are going to throw at the Eagles this season.
"I did some [pass-blocking] at Washington," Polk said. "Not a lot, but enough to get my feet wet with it. But here it's a whole different ballgame. Completely different.
"As a running back, it's important. You don't want to get your quarterback getting hit out there. You don't want anything happening to him. It's a passing league. You need your quarterback.
"I'm getting a little more comfortable with it. Just the overall knowledge of the position, the game. The understanding of why plays were called and why we ran them. The more you know, the less you have to think."
Contact Paul Domowitch at firstname.lastname@example.org