The Buccaneers are awaiting results from an MRI before determining how long Jensen will be out.
"We don't know the severity of it, per se, but I do know he'll miss some significant time, up to a couple months," Bowles said. "Whether he'll be back later in the season, November or December, depends on what they find. But he won't be available any time soon."
Jensen was injured during a team period Thursday, with the whole team gathering around him before he was carted off the field.
"He's really our enforcer when you think about it, of our offense," wide receiver Mike Evans said of Jensen. "Such a great guy, a great teammate. He brings that energy. I pray for him and his family. We'll definitely miss him. ... We're gonna miss him a lot."
Bowles said the Buccaneers will look for Robert Hainsey or Nick Leverett to step up while Jensen is out. The team has also discussed bringing in a veteran center, but he has to be the right fit, Bowles said.
"That'll be a tough battle going in -- both are very smart, both are very tough, so better to happen now than in the middle of the season so each guy can get some practice reps and prepare for it, and I think either one of them would be fine," Bowles said.
Hainsey is a 2021 third-round draft pick out of Notre Dame who converted from right tackle to center last year, seeing action in four games with 29 offensive snaps with Blaine Gabbert.
"The way Ryan approaches every day and every game is a mentality that he's the baddest dude on the field. And he usually is," Hainsey said. "Being that guy, you see it throughout the games and I know you guys like to talk about it, but being in that locker room and I think in locker rooms all across the NFL -- that means something and that carries a certain level of respect. 'He's that guy that won't let you get away with anything.'"
"I'm not Ryan Jensen, that's not who I'm trying to be. I have to be myself. But that chip on his shoulder that he plays with -- if I'm out there, I think I wanna have a little bit of that myself because I owe that to him and whoever's out there owes that to him to continue that presence of the type of man and the type of player he is on the field."
Leverett is a 2020 undrafted free agent out of Rice who spent significant time on the practice squad and has learned to back up all five offensive line positions. He started against the Indianapolis Colts last season at right guard, seeing action in two games total.
"It's always hard to see a teammate go down -- especially Ryan Jensen. He's my role model. He's a great leader and he's a guy I truly look up to," Leverett said. "I love the way he plays, I love the way he studies, I love everything he does. For me, just to see him go down -- it took an emotional toll on me. But I know Ryan, I know how hard he works at everything and I know he's gonna be back soon."
Jensen, 31, agreed to a three-year deal with the Buccaneers in March -- becoming the first Buccaneer free agent re-signed this offseason. He was among the first people quarterback Tom Brady phoned to inform of his decision to return. He surrendered only two sacks in the 2021 regular season and postseason combined and had produced a 93.1% pass block win rate from the center position -- regular season and playoffs combined -- the past two years protecting Brady.
Jensen joined the Buccaneers as a free agent in 2018, moving from guard to center, with his 4,518 snaps at the position the most of any offensive lineman since 2018.
The Buccaneers' offensive line -- one of the most durable in the league with Brady -- has seen a lot of turnover this year, losing right guard Alex Cappa to the Cincinnati Bengals in free agency and left guard Ali Marpet to retirement.
Originally drafted by the Baltimore Ravens in the sixth round of the 2013 draft, Jensen has appeared in 100 games with 90 starts in eight seasons.