FOXBORO — Christian Barmore knows the frightening diagnosis he received back in July could have ended his football career — or even killed him.

So to say he felt grateful to be back on the field Sunday at Gillette Stadium would be an understatement.

Barmore made his season debut in the Patriots’ 28-22 loss to the Los Angeles Rams, playing roughly 20 defensive snaps. It was the first time the 25-year-old defensive tackle had faced live contact since doctors discovered blood clots in his system early in training camp, sidelining him for New England’s first 10 games.

After the game, in his first public comments since his diagnosis, Barmore repeatedly thanked his teammates and coaches for their support during his recovery.

“(All) I can say is this, man: Never give up and don’t quit,” Barmore said. “Because there’s going to be days that you don’t want to do it. There’s going to be days that you don’t even want to come in and see people. But I told myself every day people are supporting me, people like who I am, and I love everybody here. They supported me. I had a lot of support here from this organization, especially, to help me come back.”

Barmore, who signed a four-year, $84 million contract extension in April, said his blood clots were discovered after a member of New England’s medical staff noticed that his right calf was larger than his left, prompting a trip to the emergency room. The Patriots placed him on the reserve/non-football illness list, and he did not return to practice until this past Thursday.

“Blood clots is not a joke,” Barmore said. “I had real bad shortness of breath, and it messed with me a lot. Mentally, I had my teammates, my medical team, my guy Wally that was with me every day, grinding with him. The days I just wanted to stop, he kept me going. He kept me strong. And my teammates really support the hell out of me, and I love them all — coaches and all. I told myself I was not going to lose that battle. I told myself I’m going to keep fighting, keep going.”

One especially valuable resource for Barmore was Patriots center David Andrews, who missed the entire 2019 season after doctors found blood clots in his lungs. Andrews, who is on injured reserve after undergoing season-ending shoulder surgery, was able to share his unique perspective with the young defender.

“Man, that man DA’s a legend,” Barmore said. “He just kept my head up every time I needed to talk to him. Every time I had my head down, he came up to me and he talked to me. And especially hearing his story, he just motivated me really well to keep going even stronger. Just keep fighting, keep going, don’t stop, ignore the noise, keep working on myself and make myself a better man.”

Though the rebuilding 3-8 Patriots aren’t pushing for a playoff berth, Barmore said his desire to rejoin the team for the stretch run “motivated the hell out of (him).”

“Especially my man (Jerod) Mayo, Coach Mayo, and DC (defensive coordinator DeMarcus Covington),” Barmore said. “Just my teammates, man, the support they gave me every day. I feel like anybody in the world would love to come back because this team literally supported me every time, even when my head was not up. So I told myself I’m going to come back for my team. That was just my goal, my No. 1 goal.”

When he learned that the illness would not end his season, Barmore “couldn’t go to sleep because (he) was so excited.”

As for how he performed in his first game back, Barmore said he played “all right” and was “a little rusty.” Mayo called him a “disruptive presence” and said it was “good just to see him back out there.”

Barmore finished with three tackles and no sacks as the Patriots struggled to generate pressure against Rams quarterback Matthew Stafford.

“I felt good,” Barmore said. “Still trying to get in game shape, but I felt real good. I’m still good. Really just keep grinding, man, just keep doing extra work. Stuff is out of my lungs now, thank God, and just keep on grinding. But I feel really good. I feel really good.”

Barmore was asked what he learned about himself during his recovery.

“Don’t ever take anything for granted, man,” he replied. “I could have lost my life. The doctor told me that. I got closer with God, just saying why this happened to me and all this. But God makes no mistakes, and God brings his toughest battle to his toughest soldiers. I’m a soldier. So I just told myself I ain’t going to let this beat me.”