PHILADELPHIA (973espn.com) — With star right tackle Lane Johnson caught up in the NFL's concussion protocol, it's likely second-year man Halapoulivaati Vaitai will be the starter against the 4-1 Carolina Panthers Thursday night.

Johnson left Sunday's emphatic 34-7 win over the Arizona Cardinals at halftime with the Eagles leading 21-7. Vaitai entered in the second half and ended up playing one more snap than Johnson (34 to 33) and help up pretty well, grading out as the 27th best offensive tackle for the week, according to ProFootballFocus.com.

That's steady if unspectacular and exactly what the Eagles will be looking for on the road in a tough environment against Panthers' veteran left end Charles Johnson.

Against the Cards, Vaitai actually did very well as a pass blocker with zero pressures allowed in 15 pass-block snaps per PFF but struggled a bit to create lanes in the running game, something evidenced by LeGarrette Blount's splits with Vaitai in. Blount had seven rush attempts that went left and gained 58 yards while he had four attempts behind the right side that gained just nine yards.

It's a tougher test this week because Carolina and Ron Rivera will certainly be game planning with Vaitai in mind.

"He's been working hard, getting enough reps here and there as the process goes, that's the nature of a backup role," offensive coordinator Frank Reich explained. "You have to be ready. There's no excuses. So that's what we expect, that's what we demand. He still gets a lots of physical work and we expect him to step up against a really good defensive end and play very well."

Johnson's absence from the lineup in the past has been problematic for the Eagles, who finished 2-8 without him in 2016 as he was forced to sit with a PED suspension. Vaitai filled in as a rookie for a number of those games and struggled at times, especially in a road environment where things tend to be a tick slower for offensive linemen.

Despite that Reich is confident that Vaitai will be ready this time around.

"I think he's just more confident knowing the calls, knowing the guys he's working with, knowing exactly what he's coached to do," the OC said. "He's had success against some good opponents and learned from his failures. And I just think that Big V has been playing more aggressive this year from training camp on, I just see an aggressiveness in his play that I like."

973espn.com Prediction: Panthers 27, Eagles 20 (2017 Prediction Record: 4-1, vs. spread 2-3).

TUESDAY NOVACARE NOTES:

Fletcher Cox was a full participant in practice Tuesday and the star defensive tackle could play on Thursday but with the long layoff after the game, the Eagles could also err on the side of caution against the Panthers and have Cox return on Oct. 23 for the Monday night affair against Washington.

Cox was noncommittal in the locker room when discussing his status and it seems his playing status is more gamesmanship than anything else.

Wendell Smallwood, meanwhile, was absent again from practice again on Tuesday, a clear sign he will miss a second consecutive game with swelling his knee, meaning the Eagles' RB by committee approach with continue to be spearheaded by Blount with Corey Clement and  Kenjon Barner mixing in from there. Barner will also serve as the main punt and kick returner again.

Those practicing on a limited basis Tuesday were defensive linemen Beau Allen (foot), Chris Long (foot) and Destiny Vaeao (wrist). Long indicated he will play.

Those banged-up who participated fully along with Cox were defensive backs Corey Graham (hamstring), Rodney McLeod (hamstring) and Jaylen Watkins (hamstring), as well as linebacker Jordan Hicks (ankle).

-John McMullen covers the Eagles and the NFL for 973espn.com. You can reach him at jmcmullen44@gmail.com or on Twitter @JFMcMullen

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