TAMPA — Maybe it’s the dinners with the entire defense on Thursday nights, something Gerald McCoy organized and paid for at first and other players have taken turns hosting for the past month.Maybe it’s the scheme, born out of necessity due to injuries to key players, which got safety Andrew Adams moved to linebacker when the Bucs deployed six defensive backs, mostly on third down.Maybe it’s the coaching change, with linebackers coach Mark Duffner taking over from fired defensive coordinator Mike Smith.“That energy,’’ defensive end Jason Pierre-Paul said. “We were missing it. That was it. And good playing calling, man.’’Most definitely it’s the improved pass rush, which has produced four sacks in each of the past three games, led by Pierre-Paul and Carl Nassib.Whatever the reason, the Bucs’ defense has been transformed from a sieve to a collection of stoppers that has been among the league’s best over the past six weeks.Since Week 7, the Bucs rank second in the NFL in sacks (24), are tied for third in third-down percentage (33.3) and are 10th in passing yards per game (216.3).“Well, our players have responded to a lot of different opportunities,’’ Duffner said. “We’ve put some guys in some spots based on a number of things, injuries and so forth. But the plus of it is we got a hungry group of guys, a bunch of guys who really want the opportunity to play, and when given that chance, so far they’ve responded, and so we’re anxious to see that continue.’’The defense will face its biggest test Sunday again when the Bucs host the Saints, who are averaging 34.9 points per game, second most in the NFL.Tampa Bay stunned New Orleans 48-40 in Week 1, but the Saints shook off the loss to win 10 games in a row. However, they’re coming off a 13-10 loss at Dallas on Nov. 29.“They’re going to come with some fire,’’ McCoy said.For the first six weeks of the season, the defense was the worst in the league. Injuries played a role. The pass rush was produced mostly by Pierre-Paul, who had little help. Smith was fired after a Week 6 loss to the Falcons with his defense allowing an average 34.6 points per game.Enter Duffner, who debuted by beating the Browns 26-23 in overtime. But with linebacker Kwon Alexander going on injured reserve with a torn ACL suffered against the Browns and later linebacker Lavonte David missing a few games with a knee sprain, the Bucs allowed 37 points to the Bengals and 42 points to the Panthers, both road losses.McCoy thought the defense needed to become closer and begin bonding, so he organized a dinner.“I’ve been doing this for a while, so it seemed like something needed to be done, and I did it,’’ McCoy said. “As little as people think I do around here, I’m a lot smarter and savvier than people give me credit for. It seemed like something needed to be done, and I did it, and to make it easier on guys, just let them show up.“I’m fortunate enough to be able to set things up and make sure guys that showed up had a good time. That’s all it was. Lavonte did his part the following the week and so on and so forth. It’s been helpful, and you see evidence of it.’’Meanwhile, Duffner and his staff needed to find a way to improve, especially on third down with no linebackers who excelled in pass coverage.“You’re always looking, as far as your scheme, to make the shoes fit the players or vice versa,’’ Duffner said. “So we just felt like looking at our current availability of players, that might be the way to go in terms of both pressure and coverage and everything else on third down in particular.’’Adams, cut by the Giants, joined the Bucs on Sept. 25 and began being used as a linebacker on third down in a dime package with six defensive backs, primary for his pass-coverage skills. Sunday against the Panthers, Adams’ role was expanded when Justin Evans left the game at halftime, forcing him to move to safety, where he intercepted three passes in a 24-17 win.“Andrew in particular is a football player,’’ Duffner said. “I mean, I’m not sure I’d put him at (defensive end) or (defensive tackle), but he is a guy who’s an instinctive football player and able to make plays.’’The no-names started producing. Linebacker Kevin Minter, who was cut after spending only one week with the Bucs, returned Sunday and recorded three tackles and a sack in only four defensive snaps.“We like that batting average,’’ Duffner said.When veteran Brent Grimes was unable to play Sunday due to a knee injury, the Bucs started Ryan Smith and De’Vante Harris at cornerback. Harris had been cut by the Saints in the preseason and then waived injured by Tampa Bay before being re-signed in October. He had three passes defensed against Carolina, batting down a Hail Mary on the final play.Duffner says young, hungry players such as Javien Elliott, who was signed from the practice squad and had a 50-yard interception return Sunday, have provided some increased intensity.“That’s what you love in coaching,’’ Duffner said. “You want the hungry player.’’And Sundays have become like Thursday nights — a defensive feeding frenzy.