ATLANTA -- Tampa Bay Buccaneers wide receiver DeSean Jackson ripped his helmet off in disgust. Wide receiver Mike Evans said he felt "sick."

With quarterback Jameis Winston back in the starting lineup after a three-game suspension, the Bucs' offense put up 512 yards with four touchdowns yet still couldn't come away with a win, falling to the Atlanta Falcons 34-29 and extending their losing streak to three.

"It's a game we let get away," said Jackson, who caught four passes for 77 yards but could not catch a lateral at the 5-yard line on the final play with seven seconds left. "We didn't put ourselves in a great position, but there's no way we should have lost to this team. We're a way better team than what showed up today.

"It's frustrating. We worked so hard and we've got so many great, talented guys in here but we just haven't figured out a way [to win] these last three games."

Said Evans: "It's just us beating ourselves, as usual. We had our way and we beat ourselves again. Right after the game, I was sick. Right now, I'm [feeling] a little better, but I'm still hurting about it. ... It's still early in the season. We can't hang our heads. We've got Cleveland coming to town next week. We need that one bad."

Winston had two interceptions in key moments. The first came in the second quarter on a deep pass intended for Jackson at the Atlanta 5-yard line. The second came on the opening drive of the second half, with Winston attempting to hit Chris Godwin in the end zone. Instead, the ball bounced off a defender's helmet and into the hands of Brian Poole.

"You can't turn the ball over at the 6-yard line. I think that's really gonna be the story of the game. You can't turn the ball over twice," Winston said. "No matter how good you play, you see their quarterback, he had a great game and no turnovers. They won and we lost. ... You eliminate those two plays, I had a great day. You have those two plays, it's a bad day."

Head coach Dirk Koetter added: "Jameis -- he does so many good things out there, he does so many good things. He has composure, he can make all the throws, he runs the team, he scrambles, he's tough -- but there's a couple balls you'd like to have back. That's every quarterback in the league. That's playing quarterback in the NFL so -- I think Jameis played well for a huge percentage of the game."

The defense, however, has truly become the Bucs' Achilles' heel. Many fans were furious that Koetter did not make a change at defensive coordinator during the bye week after Mike Smith's unit surrendered six touchdowns to Mitchell Trubisky in Week 4. Against the Falcons, they failed to make a stop in the red zone, allowing chunk play after chunk play.

The NFC South division began the season pretty much the same way -- with no team playing stout defense. In fact, the first three intradivisional games saw a combined 223 points -- the highest combined point total for any division's first three intradivisional games since the 1970 merger. But the New Orleans Saints' 43-19 thrashing of the Washington Redskins on Monday Night Football last week showed not only that they can play tough defense, but that at 4-1, they're the team to beat in the division.

Meanwhile the Bucs, the one team that did beat the Saints in Week 1, continue to give up over 400 yards per game. Sure, there have been injuries -- with cornerback Vernon Hargreaves and safety Chris Conte on injured reserve -- but the defense was the priority this offseason. That was the area Koetter and general manager Jason Licht were adamant about fixing.

They should have enough depth to overcome these injuries. Plus, two key pieces of the defensive line -- defensive tackles Beau Allen and Vita Vea -- have returned from injury. The defense should be getting better.

"It's frustrating," linebacker Lavonte David said. "Very frustrating. Being around these guys all day. ... I know what they're capable of. I know what type of players they are."

But now, at 2-3, it already feels like the season is starting to slip away.

"I don't know what's going on, man, honestly. I'm very frustrated," Jackson said. "I hope other guys in this locker room are frustrated. We're a way better team than this, but it's not happening. We've gotta figure it out. I don't like losing. I'm not a loser. No one else in this locker room wants to be a loser."