The Philadelphia Eagles are no stranger to serious injuries, overcoming big-name losses over the course of potentially three straight playoff runs, and now they may have to overcome one of their biggest yet.

As NFL Network’s Ian Rapoport reported Sunday, star tight end Zach Ertz suffered both a fractured rib and lacerated kidney during the Eagles’ crucial victory over the Dallas Cowboys in Week 16. The team’s leading receiver has not been ruled out for next week, when Philly could host a playoff game, per Rapoport, but The Philadelphia Inquirer’s Jeff McLane has since reported Ertz’s season is “likely over” because of the lacerated kidney.

According to UpToDate, a resource tool for physicians and patients, a lacerated kidney puts Ertz at risk of losing his kidney regardless of whether he returns to the field during the Eagles’ potential playoff run. Depending on the severity of the injury, Ertz might be recommended to rest from contact sports for at least a month — perhaps even six weeks, at the minimum, according to a medical source — meaning an end to the tight end’s 2019 season, though McLane also said Sunday the veteran had been preparing this week to play against the New York Giants in Week 17.

If the Pro Bowler would’ve shown worse and/or immediate signs of a serious laceration, such as blood-pressure issues or internal bleeding, he likely would’ve had his kidney surgically removed by now, per the resource tool. A low-grade kidney laceration, which appears to be what Ertz is dealing with, would likely heal on its own, but that kind of recovery would also require further monitoring from doctors. Chances of re-injury would obviously increase if Ertz were to return to the field.

It remains to be seen whether the tight end simply attempted to play through the injury this week or whether the Eagles’ team doctors did not immediately recommend that he remained sidelined. The Philadelphia Daily News’ Les Bowen cited two separate medical sources Sunday in suggesting the club “should have suspected” the injury during the Eagles-Cowboys game and kept Ertz from returning, which he briefly did.

The 29-year-old tight end leads the Eagles with 88 catches for 916 yards in 2019, consistently serving as quarterback Carson Wentz’s top target in an offense that’s been riddled with wide receiver injuries and tailored more to short, quick passes. One of Philadelphia’s most reliable pass-catching options for a half-decade, Ertz broke the NFL‘s all-time record for most catches by a tight end in a single season with 116 in 2018, when he posted a career-high 1,163 yards and eight touchdowns.