Playing for the first time since a bullying scandal, the Dolphins were defeated 22-19 by the Buccaneers on Monday night.
Miami (4-5) started slowly before overcoming an early 15-0 deficit to lead 19-15 heading into the fourth quarter.
"I felt like we've really come together over this adversity," Tannehill said. "This could have gone two ways. Guys could split up and start taking sides and divide the locker room, or we could come together. I feel like we came together this week."
The Dolphins had not played since Oct. 31, when they beat Cincinnati 22-20 in overtime to stop a four-game skid.
They've been the talk of the league for the wrong reasons ever since.
The NFL is investigating tackle Jonathan Martin's allegations of daily harassment by teammates, including suspended guard Richie Incognito. Martin is with his family in California to undergo counseling for emotional issues, and he'll meet later this week with the league's special investigator to discuss the allegations.
The special investigator will determine whether Incognito harassed Martin, and whether the Dolphins mishandled the matter.
"It wasn't about distractions," Miami cornerback Brent Grimes said. "The Bucs came out and played a good game. They made more plays than we did. That's why they won. It was nothing to do with all the stuff that's going on. None of that. They just made plays."
Owner Stephen Ross broke his silence on the situation during a news conference before the game at Raymond James Stadium. He said he was appalled by the player's accusations and plans to meet with Martin on Wednesday at an undisclosed location.
"Obviously there was a voice we weren't hearing," Ross said, adding he will take an open mind into the meeting and is eager to learn the facts of the case.
The owner said he has formed an independent advisory group that includes Tony Dungy, Don Shula, Dan Marino, Jason Taylor and Curtis Martin to review organizational conduct policies and to make recommendations on areas for improvement.
"We need to look at ourselves. We have to examine everything internally," Ross said. "This is so appalling to me. I know I'm capable of overreacting. I want to get everybody's feedback because we all know the football locker room is a different workplace than most of us are accustomed to. I don't want to make any excuses."
"They deserved to win the game," Dolphins coach Joe Philbin said. "We didn't play well enough in any phase of the game ... Offense, defense or special teams to win the game. We had plenty of opportunities. They had better tempo. They controlled the line of scrimmage better."
Bobby Rainey's 1-yard run capped an 80-yard drive, and the Bucs held on the final 10 minutes to become the last team in the league to win this season.
Jacksonville beat Tennessee on Sunday, leaving Tampa Bay (1-8) as the league's only winless team entering the game.
"It's good to stand up here after a win," Bucs coach Greg Schiano said after his team won for only the second time in 15 games dating to last season. "We have to build off this."
Glennon completed 11 of 21 for 139 yards in his sixth pro start. The third-round draft pick threw his first interception in four games — a span of 159 attempts — to set up a third-quarter field goal that put the Dolphins up 19-15.
Tannehill finished 27 of 42 for 229 yards, two touchdowns and an interception.
Glennon finished a nine-play, 76-yard, game-opening drive with his TD pass to Penn, a 6-foot-5, 340-pound tackle who discreetly slipped off the line and was all alone in the end zone. Mike James ran five times for 41 yards on the drive before leaving the game with a broken left ankle.
The Bucs built the lead to 15-0 with a pair of field goals by Rian Lindell and a safety before Tannehill got the Dolphins on track in the closing minutes of the second quarter.
Tannehill trimmed his team's deficit to 15-7 with his first TD pass to Matthews. The second put Miami ahead 16-15 late in the third quarter.
"We moved the ball well through the air but we didn't have any balance. That caught up to us at the end of the game," Philbin said. "There's a lot of football left to be played. November and December is going to determine who moves forward," Philbin said. "We have to learn from the mistakes we made and prepare better and play better."
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