It's hard enough for a player to come back and play the week after sustaining a concussion. It might be impossible on a short week.
That's the situation the Eagles find themselves in after Lane Johnson went down against the Cardinals with a Thursday night matchup in Carolina looming.
"It's tough based on the protocol and what the players have to go through," head coach Doug Pederson said. "Again, I'll find out this afternoon, but it's hard on a short week."
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Pederson confirmed on Monday that Johnson did indeed suffer a concussion against the Cardinals and has entered the NFL's concussion protocol. The timing of the next game should keep him out for at least one game.
Johnson suffered his concussion sometime during the first half and didn't come back for the second. Pederson didn't specify when in the first half the injury occurred. Unless Johnson was concussed on the final play of the half, Johnson played at least some time on Sunday with a concussion.
With Johnson's injury, Pederson said he'll install this week's game plan with Halapoulivaati Vaitai as the team's starter at right tackle.
Vaitai entered the game in the second half on Sunday. He played 34 snaps and didn't give up a sack, quarterback hit or quarterback hurry.
"Big V came in and started the third quarter and we went down and got the points right away," Pederson said. "He played good, played solid. He's one that the more he plays, the better he gets. Even on a short week, for him not getting a ton of reps at tackle, to come in off the bench like he does, it's just a tribute to the way he prepares himself, the way he battles. Gets better every time he's out there."
Vaitai's pro career got off to a disastrous start last year. He took over for Johnson in the Eagles' fifth game of the season and was man-handled by Washington pass-rusher Ryan Kerrigan. But after that game, Big V slowly got better. He hoped to prove himself in the NFL.
"I was still a rookie, but when I got thrown into the fire, I learned real quick that if you're not doing great, then you're out," Vaitai said this June. "I didn't want to be a disappointment to my family and be that guy who gets drafted and then is out the next year."
He'll get another chance to prove himself on the road against a good Panthers team on Thursday.
Including Sunday's win, the Eagles are 9-2 over the last two seasons when Johnson plays. They are 2-8 without him.