New England Patriots v New York Giants
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The Patriots were down to two healthy cornerbacks in Sunday's loss to the Chiefs, in part because veteran J.C. Jackson did not take the field. While coach Bill Belichick declined to elaborate on Jackson's absence from the lineup after the game, Jackson's agent told ESPN the former Pro Bowler is dealing with mental health issues.

"He wasn't available," Belichick initially told reporters. "Leave it at that."

Jackson was active for the game but did not take a single snap. Teammates also told reporters afterward they didn't realize Jackson would be unavailable until the start of the matchup, which New England lost 27-17. 

On Tuesday, the Patriots placed Jackson on the reserve/non-football illness list. That likely ends his season, per NFL Media.

It marks the latest turn in a tumultuous season for Jackson, who rejoined the Patriots via trade in October. The former All-Pro, who totaled 17 interceptions from 2020-2021, notably didn't travel with the team for a Week 10 game in Germany. He was also benched the week prior, reportedly as a punishment for missing curfew at the team hotel.

Jackson only returned to New England because of a falling out with the Chargers. Signed to a five-year, $82.5 million deal by Los Angeles in 2022 free agency, the Maryland product missed the start of his Chargers debut after undergoing ankle surgery, then was briefly benched halfway through the season. A knee injury limited him to just five games total, and he again bounced in and out of the lineup to start 2023, until L.A. made him a healthy scratch and shipped him back to the Pats.

Jackson was also the subject of a Massachusetts arrest warrant this September, facing a criminal speeding charge from 2021.