It's getting to the time of year when NFL injuries pile up to the point that makes everyone in the football world's heads spin. Fans, coaches, players, and executives alike must grapple with an ever-changing landscape as the playoffs approach, with teams pivoting to backups at several key positions.

Week 15 was particularly brutal, as there was a mix of season-ending, week-to-week, and day-to-day injuries to some of the biggest names in the NFL. When will they all return?

Kansas City Chiefs QB Patrick Mahomes

Mahomes went down in the fourth quarter of the Chiefs' 21-7 victory over the Cleveland Browns and didn't return. The three-time Super Bowl champion is considered week-to-week, via NFL Network's Ian Rapoport.

“Sources: Chiefs QB Patrick Mahomes was diagnosed with a mild high-ankle sprain following tests, and he’s still considered week-to-week. Tests confirmed initial thoughts,” Rapoport reported. “The schedule is tough, with a Saturday game then a quick turnaround for Christmas.”

However, Mahomes hasn't yet been ruled out for Week 16, via Rapoport.

“The Chiefs will know more as the practice week rolls on, and there is a chance that Patrick Mahomes practices this week,” Rapoport said. “He's week-to-week, so his status this week is in doubt.”

A source also told Rapoport that Mahomes will be “fine long-term,” which should bring down the state of Missouri's collective blood pressure. However, head coach Andy Reid and company may opt to sit the future Hall-of-Famer to be safe.

With Kansas City's upcoming slate of three games in 11 days, backup quarterback Carson Wentz might have to recapture some 2016 magic to keep the team on track ahead of the playoffs. Luckily for the Chiefs, their 13-1 record gives them breathing room ahead of the grueling stretch against the 9-5 Houston Texans, 10-4 Pittsburgh Steelers, and 9-5 Denver Broncos.

They've already clinched the AFC West and are two games ahead of the Buffalo Bills atop the conference. Kansas City will secure a first-round bye and home-field advantage in the playoffs if they finish as top seed.

New Orleans Saints RB Alvin Kamara

Kamara is in the midst of another top-notch campaign, ranking 10th in the NFL with 950 rushing yards while adding 89 catches and 543 yards through the air. However, the 29-year-old's momentum may be halted, via ESPN's Katherine Terrell.

“[Saints interim head coach] Darren Rizzi said Alvin Kamara's injury is a groin abductor type of situation. He said it felt minor and he felt it on the touchdown, but he's going to continue to go through tests,” Terrell reported. “But then when asked if it was minor, Rizzi said he wasn't going to make a medical declaration.”

Kamara got hurt during his 21-yard touchdown reception from wide receiver Cedrick Wilson Jr. on a trick play in the Saints' 20-19 loss to the Washington Commanders. While the Tennessee alum's timetable is still unclear, the star tailback can at least take solace in the fact that this isn't a contract year for him, as he signed a two-year extension in training camp. While his season could be derailed with three weeks left, this ailment won't hurt his pockets.

Detriot Lions RB David Montgomery

David Montgomery cries in Lions gear

Speaking of running backs, Montgomery is one of the unluckiest players on this list. The reliable veteran is officially out for the season with a sprained MCL, via ESPN's Adam Schefter.

“Now confirmed: Lions HC Dan Campbell said RB David Montgomery will undergo season-ending knee surgery,” Schefter said. “We're going to miss him,” Campbell told reporters.

Montgomery is a crucial part of this injury-ravaged Lions team, and his absence could hurt their chances in the playoffs. The former Chicago Bear is the thunder to Jahmyr Gibbs' lighting in Detroit's backfield, making for the best one-two punch in the NFL. Montgomery finishes the season with 775 rushing yards and 12 touchdowns on 185 carries, as well as 38 catches and 341 receiving yards.

The 27-year-old went down during the Lions' 48-42 loss to the Buffalo Bills on Sunday, which downgraded them to 12-2 on the season.

Detroit is now stuck in a logjam atop the NFC with the 12-2 Philadelphia Eagles and 11-2 Minnesota Vikings, and it has to stay afloat with one of the longest injury lists in the NFL. The defense is especially damaged, with edge rusher Aidan Hutchinson and linebacker Alex Anzalone just two of the prominent players on injured reserve, via ESPN.

Dallas Cowboys CB Trevon Diggs

Diggs, who is the star of Dallas' secondary, is also getting season-ending knee surgery, via Rapoport.

“Cowboys CB Trevon Diggs will have surgery to repair an issue related to his articular cartilage, source said. His recovery could take up to 8 months,” Rapoport reported.

The shutdown corner finishes the year with 42 tackles and two interceptions in 11 games played.

Cleveland Browns RB Nick Chubb

Add Chubb to the list of NFL running back injuries once again. Less than two months after returning from a devastating knee ailment he suffered in Week 2 of the 2023 season, the four-time Pro Bowler is out for the year with a broken foot, via the NFL's social media.

Browns head coach Kevin Stefanski believes Chubb's foot may have been stepped on in the third quarter of Cleveland's loss to the Chiefs, via ESPN's Daniel Oyefusi.

The 2022 second-team All-Pro could be done with the Browns after seven seasons with them, as he will be an unrestricted free agent in the offseason.

Pittsburgh Steelers LB T.J. Watt

TJ Watt looks sad in Steelers gear

Watt suffered a low-ankle sprain during the Steelers' 27-13 loss to the Philadelphia Eagles. However, Pittsburgh coach Mike Tomlin said that the “door is ajar” for the former Defensive Player of the Year to play against the Baltimore Ravens on Saturday, via Pro Football Talk's Myles Simmons.

“T.J. Watt, I just saw him walking around rather comfortably,” Tomlin said. “But, again, he’s questionable with his ankle, we’ll see where the roads lead us.”

Watt is having another banner season as the Steelers' defensive anchor, as he's tied for third in the NFL with 11.5 sacks and leads with six forced fumbles.