The New England Patriots placed Christian Barmore back on the reserve/non-football injury list on Thursday. The standout defensive tackle experienced recurring symptoms related to blood clots he dealt with earlier this year that require further evaluation.

“We appreciate everything Christian did to return to the team this season, but our top priority is Christian’s health and wellbeing,” the Patriots said in a statement. “We know that he will continue to receive tremendous care and we want to ensure that he gets the time he needs to come back stronger than ever.”

Barmore missed the first 10 games of the season due to blood clots. Last season he had 8.5 sacks, 64 tackles and 16 quarterback hits. He also had a career high 13 tackles for loss.

In the offseason, Barmore was rewarded with a four-year extension worth up to $92 million with $41.8 million in guaranteed money. The deal made him the highest paid defensive player in team history.

It was unclear if Barmore would even play this season after doctors found blood clots in his lungs at the start of training camp.

“Blood clots is not a joke because I had real bad shortness of breath. It messed with me a lot,” Barmore said. “I told myself I was not going to lose that battle. I told myself I’m going to keep fighting, keep going.”

In four games this season, Barmore had one sack and six solo tackles.