TAMPA, Fla. -- Throughout training camp, Tampa Bay Buccaneers head coach Bruce Arians downplayed the significance of quarterback Jameis Winston's interceptions in practice -- including days when he had multiple picks -- deeming them a function of Todd Bowles' unpredictable defense and the offense learning a new system. During a 31-17 loss to the San Francisco 49ers, however, it was clear that Winston and the offense are still trying to figure things out.

Turnover machine: Winston was intercepted three times. The first bounced out of tight end O.J. Howard's hands and into the hands of linebacker Mark Nzeocha. The second was a pick-six by cornerback Richard Sherman on a pass where running back Peyton Barber appeared to lose his footing.

The third came late in the fourth quarter, with 2:01 remaining, when Winston had a chance to orchestrate a game-winning drive. Cornerback Ahkello Witherspoon picked him off on a screen pass and returned it 25 yards for a score. Winston was nearly picked off a fourth time by Kwon Alexander, but it was dropped.

It was Winston's 17th career game with multiple interceptions, passing Blake Bortles for most in the league since Winston entered the NFL in 2015. This is also a Niners squad that had a total of two picks in 2018 -- the fewest of any defense in NFL history. Winston also becomes just the third player with multiple pick-sixes in a season opener in the last 15 seasons, along with Joey Harrington (2007) and Scott Tolzien (2017).

Sloppy day for the offense: When the Bucs were able to move the ball and sustain drives, they were slapped with penalties, wiping out, not one, but two Cameron Brate touchdowns on the same drive -- both holding calls on Demar Dotson. Also on that drive, Howard fumbled the ball at the 49ers' 8-yard line. The one bright spot came in the third quarter. Winston scrambled to his right and found Chris Godwin on the move for a 10-yard touchdown to make it 20-13.

Defense looks much improved under Todd Bowles: The Bucs' shift to a more aggressive, attacking defense under Bowles looks to already be paying off, even when put into unfavorable positions by the offense. This was the most prepared this unit has looked in several years. At no point did they look surprised, which was a common occurrence under previous defensive coordinator Mike Smith.

With 8:47 to go in the second quarter, on second-and-18, cornerback Vernon Hargreaves jumped a hitch route by Tevin Coleman, picking off Jimmy Garoppolo and returning it 12 yards for a touchdown to grab a 7-6 lead. It was just the second interception of Hargreaves' career. Hargreaves has said all summer how much more confident he is in this system, something several of the Bucs' young defensive backs have echoed, including Carlton Davis, who recovered a Deebo Samuel fumble that was knocked loose by Devin White.

The Bucs did, however, surrender a touchdown to the Niners in the second half, with Richie James outrunning nickel back M.J. Stewart one-on-one on a 39-yard touchdown.

Quick turnaround: The Bucs face a huge test by hitting the road Thursday night to play NFC South foe Carolina, a group that hung close with the LA Rams in a 30-27 loss. Last year, teams playing on the road on Thursday went 4-13. Arians also acknowledged that the first regular-season game is typically a shock to the body, making recovery that much more of a challenge since they played so little in the preseason. "There's no doubt," Arians said. "We'll start recovery in the locker room after the game." Mike Evans caught just two of his five targets for 28 receiving yards against the 49ers. He faces James Bradberry next week, a cornerback who held him to a season-low 16 receiving yards in Week 9 last year.