The Bucs (1-1) rebounded from an embarrassing four-touchdown season-opening loss to Tennessee, with Smith keying a superb defensive effort that stifled Drew Brees and the New Orleans Saints in a 26-19 victory.
A little over a year after being claimed off waivers from the Buffalo Bills, Smith woke up Monday as the NFL sack leader with four through two games.
He took down Brees three times, forcing two fumbles Sunday, as Tampa Bay's defense finally began to show signs of being capable of doing its part to help rookie Jameis Winston develop into a successful NFL quarterback.
''It's a little different world from where I came from last year,'' Smith said. ''But I think I felt better just waking up and seeing the guys smiling in the locker room from a great victory we had. We really went up there and earned it. Pretty much hats off to the whole team because everyone played a part in it.''
The Bucs sacked Brees four times overall and forced three turnovers, doing what they were unable to do very often last season - generate a consistent pass rush and shift the momentum of games with timely takeaways that Lovie Smith-coached teams are known for.
''We saw marked improvement. ... Defensively, guys came out strong,'' Lovie Smith said, noting how much better the Bucs performed after being shredded by the Titans during a 42-14 loss to the Titans the previous week.
Marcus Mariota threw for four first-half TDs in his regular season debut, and Tennessee scored on five of its first six possessions against a defense that seemed unprepared.
The Bucs insisted it was just one game, vowing to bounce back against the NFC South rival Saints (0-2).
''It's big for us to get that first division win,'' Jacquies Smith said. ''It's big for the confidence, and I commend the guys for going to work the last week, having a good practice week and it showed out there on the field.''
The 6-foot-2, 260-pound defensive end entered the NFL as an undrafted college agent with Miami in 2012. He spent 11 weeks on Buffalo's practice squad in 2013, then the entire 2014 offseason on the Bills roster.
He joined the Bucs in Week 2 last year and wound up appearing in 15 games, with seven starts as a rookie. His 6 1-2 sacks over the final eight weeks of the season tied for the 10th-most in the league over that span.
''I've come a long way from the journey that I've been on, but it is what it is,'' Smith said.
''Being here for a year last year, I feel like I'm more comfortable in the system and more comfortable around here,'' he added. ''I feel like I can play a lot faster than even what I did last year. It's helping me a lot just getting that continuity with the guys in the locker room and the coaches.''
Sunday's breakout performance left the young pass rusher's name alone atop the NFL sack list. Houston's J.J. Watt, Kansas City's Justin Houston, New England's Chandler Jones and Tennessee's Derrick Morgan all have three.
''It wasn't just Jack. I thought we rushed the passer well,'' Lovie Smith said, adding the defense also took a step forward by keeping the Saints out of the end zone in the closing seconds to win.
''We needed to cross that hurdle because we haven't been able to. ... It should definitely give us confidence,'' the coach said.
''Now, for us, that next step - based on what we've done in the past around here - is follow that up with another good performance this week,'' Lovie Smith added. ''That's our plan.''
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