The Philadelphia Eagles are on the brink of the playoff picture despite losing a critical battle for first place in the NFC East in Week 14, but it appears they'll be without their most important player when they visit the Los Angeles Rams on Sunday.

Head coach Doug Pederson announced Wednesday a surprise addition to the team's injury report for Week 15 -- quarterback Carson Wentz, who missed the day's practice with back soreness. Pederson would not commit to Wentz playing against the Rams, saying the team would "focus on today and getting him better." And NFL Network's Ian Rapoport suggests the injury could be even more severe -- or the team even more cautious -- than Pederson indicated, reporting via Twitter that Wentz isn't likely to play Sunday and could even miss the remainder of the 2018 season depending on the result of the Rams game.

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The Eagles have been no stranger to injuries in their defense of a Super Bowl title this season, losing running back Jay Ajayi, wide receiver Mike Wallace, defensive end Derek Barnett, cornerbacks Jalen Mills and Ronald Darby and safety Rodney McLeod among others to Injured Reserve. Wentz's ailment, however, is a curious one considering the magnitude of this week's game and the fact the quarterback had not missed a practice since being given what the team deemed "rest" days in October, as The Philadelphia Inquirer's Jeff McLane reported.

"The Eagles did their best to downplay it," McLane wrote on Twitter. "Not a stretch to say that it's been bothering him for months, and could be the reason he hasn't looked his normally freakish athletic self."

Pederson and the Eagles' medical staff, which underwent an overhaul entering this season, have been about as vague as can be in describing injuries throughout the season, including Wednesday's confirmation of running back Corey Clement's move to IR. The sudden announcement of Wentz's issue follows suit, leaving fans to wonder whether the team's franchise quarterback will be available for even a single game of a make-or-break stretch toward a potential Wild-Card berth.

The back injury also raises more questions about Wentz's durability. The former No. 2 overall draft pick and 2017 MVP candidate suffered a torn ACL last December while helping the Eagles clinch a playoff spot against the Rams, missing the team's final six games -- including the postseason -- on the road to a Super Bowl LII victory. He then remained sidelined for the first two games of this season while recovering from surgery and has returned to middling results -- a career-best completion percentage and respectable passing marks, albeit on a disappointing offense with occasionally limited mobility.

In the event Wentz sits against the Rams and/or the remainder of the Eagles' season, veteran backup and Super Bowl LII MVP Nick Foles is set to start for Philadelphia. Foles first saw action in relief of Wentz against the Rams in 2017 and then proceeded to guide Philadelphia through the playoffs with historic performances in the NFC Championship and Super Bowl. This year, he's started two games, going 1-1 to start the year against the Atlanta Falcons and Tampa Bay Buccaneers.