The Bucs placed the fourth-year pro on injured reserve Tuesday, the third time in Howard's career that an injury has ended his season prematurely.
Howard, the 19th overall pick in the 2017 draft, had 11 receptions for 146 yards and two touchdowns in four games, helping the Bucs to a 3-1 start. He had a 28-yard TD reception before being injured early in the fourth quarter of last week's 38-31 victory over the Los Angeles Chargers.
Howard will be replaced in the lineup by Cameron Brate. The sixth-year pro has 28 career touchdown receptions but hasn't played much this season with Howard and Rob Gronkowski handling most of the tight end duties in the Tom Brady-led offense.
''You can't replace him. You just put the next guy in and put in the game plan what he does best,'' coach Bruce Arians said.
''Cam Brate, Tanner Hudson. Those guys can do things, too. But they can't be O.J. O'J.'s a special guy,'' Arians added. ''Obviously, we'll sorely miss him. But one man's injury is another man's opportunity.''
Brate has 196 career receptions for 2,159 yards. His lone catch this season, a 3-yarder against the Chargers, was for a touchdown.
Brate's role will increase beginning Thursday night against the Chicago Bears.
''I feel terrible for O.J. He's playing great. ... But that's kind of the nature of the beast,'' Brate said. ''I was kind of biding my time for a little bit, so I feel fresh heading into the short week. I feel like I've kind of got the leg up on everyone else. I haven't been playing too much.''
Brady said Howard will be missed. He also predicted the 6-foot-6, 250-pound tight end will overcome the injury, resume his career and be ''better than ever.''
''He's a very talented player and he's got a great attitude. He brings his best every day. He's dependable, consistent. To lose a guy like that is a big blow for all of us,'' Brady said.
''We're all supportive of him, what's ahead of him,'' the quarterback added, ''which I know he'll overcome.''
Howard's rookie season was cut short by an ankle injury. Leg and ankle injuries also sidelined him past two years.
Through four seasons, he has 105 receptions for 1,602 yards and 14 TDs in 42 games.
Wide receiver Cyril Grayson was signed from the practice squad to fill the roster opening.
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