Dirk Koetter spoke with the press on Monday afternoon, less than 24 hours after the Tampa Bay Buccaneers finished off a 28-21 victory in San Diego and moved into a tie for first place in the NFC South. In the interim, Koetter had an opportunity to review the tape from that game and gain a more detailed understanding of how the Bucs won their fourth straight.

So, upon further review, here are a few things Koetter and the rest of us learned from – and/or what new questions were raised by – the Buccaneers' Week 13 victory over the Chargers.

1. Improvement in the second half saved the Buccaneers in San Diego but a better all-around effort will likely be needed to stop New Orleans this coming weekend.

The visiting team scored 21 of the last 28 points in Sunday's game at Qualcomm Stadium, most of which was necessary to pull out a win on a day that started off slowly for the Buccaneers.

Tampa Bay trailed 14-7 at halftime and, after briefly taking a lead in the third quarter, was down 21-17 heading into the final period. For just the second time all season, the Buccaneers came back from a halftime-deficit to win, and that was the team's first win this year in which it trailed after three quarters. Jameis Winston's 12-yard touchdown pass to Cameron Brate and Keith Tandy's goal-line interception were enough to get the Bucs out of San Diego with their fourth straight victory, but Koetter didn't think his team played as well as it had the previous three weeks.

"After looking at the tape, I don't think we played great yesterday," said the coach. "We got the win, but when you really look at it, did we do anything? We made plays when it counted and the back-to-back plays of Bryan Anger's punt down to the 7-yard line and then the pick-six on the next play, those two plays flipped the momentum back because we were really just kind of hanging on for a big part of that game."

Lavonte David provided that pick-six and only had to run 15 yards to the end zone because Anger's 54-yard blast had pinned the Chargers back by their goal line. Before that, the Bucs had settled for a field goal after a long drive to open the half and had gone three-and-out on their other possession. Things picked up after that as the offense scored on its next two possessions after San Diego had taken the lead back with a long touchdown pass.

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"And then I thought we finished the game well," said Koetter. "I thought we played better overall in the second half, but I don't think we played overall as well in that game than as we had the last three weeks. And I know for a fact we're going to have to play better against New Orleans."

Of course, one could look at that assessment optimistically and believe the Buccaneers have progressed to the point where they don't necessarily have to put forth their best possible effort in order to win. With second-year quarterback Jameis Winston playing very well and exerting his leadership in a positive fashion, and with the defense continuing to be optimistic with the takeaways week after week, a confident Buccaneer team is beginning to believe it has a chance to win every game.

* 2. Two rookie cornerbacks are making big strides.*

The Buccaneers currently have five cornerbacks on the roster, and two of them are in their first NFL seasons. Of course, one was the 11th overall pick in the 2016 NFL Draft while the other went undrafted and didn't sign with the Buccaneers until nearly June.

Obviously, Vernon Hargreaves and Javien Elliott have somewhat different backgrounds, although they're both Florida kids who played for powerhouse college programs in the state. Hargreaves was a three-time All-SEC first-team pick, an All-American in 2015 and a finalist for the Jim Thorpe Award while playing at the University of Florida. Elliott walked on at Florida State and didn't see the field until last season.

Hargreaves has been a starter since Day One for the Buccaneers while Elliott spent  most of the season on the practice squad before cornerback Jude Adjei-Barimah received a four-game suspension from the league. Now they're playing together in Tampa Bay's secondary, or at least they were for the majority of Sunday's win over the Chargers.

Hargreaves has barely missed a defensive snap all season but his role in the defense has changed over time. He began the year in a dual-capacity role, playing an outside corner spot in the base defense and moving into the slot in the nickel package. In Week Three, the coaching staff chose to move Hargreaves exclusively to the outside, where he played at Florida, and inserted Adjei-Barimah into the nickel back role.

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When Adjei-Barimah became unavailable, the team went back to the original plan, but then chose a different approach when Sunday's game didn't get off to an optimal start. Alterraun Verner, who had an extremely impactful performance in last week's win over Seattle, struggled a bit Sunday, which Koetter chalked up to a very difficult two weeks. Verner's father passed away unexpectedly the day after Thanksgiving, just two days before the Seattle contest, and Verner planned to stay in California for services after the San Diego game.

So Elliott came in to play the slot an Hargreaves switched jobs midstream. Hargreaves also took over as the punt returner after injuries to Adam Humphries and Cecil Shorts.

"Think about all the things Vernon did yesterday," said Koetter. "He started the game at nickel when they were in 11-personnel, he started at corner, he was also starting at nickel and then we made a switch partway through the game and brought Elliot in at nickel and Hargreaves went back outside, did a good job with all that. We lose our top two punt returners in the first half and he comes in and…one of our goals for the game was to field every punt because their punter had kind of been spraying the ball. He was playing it like 50 yards deep and that last punt he caught, he had to come up 15 yards to catch it. If that ball hits the ground, that saves 15 yards, that's an explosive play. He wore a lot of hats yesterday and one of the hats you're not expecting him necessarily to wear is that of leader."

That last remark referred to postgame discussions about Hargreaves' role in diagnosing several Charger plays and successfully communicating the information to his teammates. The team's four-game winning streak has followed a pair of painful losses in a five-day span in which the defense had several breakdowns attributed to communication problems.

"It's been well documented about the improved communication on our defense," said Koetter. "[Now there are] reports of his communication on two huge plays, maybe the two biggest plays in the game, two of the biggest plays. The biggest difference that I've noticed in Vernon since the mini-bye, was it seems like he's having fun out there. Sometimes rookies have to pay their homage to the leadership of the team to the veterans, but more than anything, I think Vernon's just having fun out there."

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Meanwhile, Elliott's remarkable rise from college walk-on to NFL contributor continues, as he took part in 42% of the Bucs' defensive snaps on Sunday and obviously held his own. His promotion from the practice squad might have seemed like an emergency depth move after the Adjei-Barimah suspension, but the Bucs didn't bring him up with the intention of keeping him on the bench.

"The main reason we have confidence in Javien Elliott is he picks off our offense about three times every day in practice," said Koetter. "He's a kid that practices hard – we encourage those guys not to hit our guys, not to take shots on our guys, but if you can get the ball in practice, get it, and nobody picks off Jameis Winston more than Javien Elliot. And he make plays, so we knew when he had a chance to come up, that we weren't going to be afraid to put him in the game."

3. The running game is still not producing at an optimal level but Charles Sims should be back soon to help out.

Tampa Bay's rushing attack topped out at 81 yards and 2.7 yards per carry against the Chargers, but it wasn't for a lack of trying. The Buccaneers ran the ball on 14 of their 24 first downs (not counting an end-of-game kneel-down by Winston), though not often to good effect. Only five of those carries gained at least four yards, and eight of them were stuffed for two yards or less. Lengthy injury absences for Doug Martin, Charles Sims and Jacquizz Rodgers have obviously been one of the main factors, but the team has still not regained the ground game that was so effective a year ago, with much of the same cast.

"We're not as productive in the running game as we'd like to be," said Koetter. "San Diego did some things, movement-wise with their front. When we were in our three-wide personnel, they loaded the box on us and we maybe got a little ahead ourselves, trying to keep some runs against some bad box counts, when we maybe should've given Jameis the option to get into a pass play. And that's not Jameis's fault, that's my fault. I think you've got to give San Diego a little credit, but I do think we can run the ball better and we're going to need to run the ball better."

Martin has been back for four games now and has a total of 228 rushing yards (and two touchdowns) in that span. Koetter has consistently said that he does not believe the ground-game struggles are due to Martin playing poorly; in fact, he has praised Martin's pass-blocking, and the fifth-year back has often made more out of some carries than the average runner would, such as his second-effort touchdown run on Sunday. Martin has also contributed several big plays in the passing game since his return.

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The Bucs may be in good position to rediscover that power rushing game down the playoff-race stretch. Not only is the original offensive line back intact after a few health issues, but the backfield is about to be loaded. Koetter said on Monday that he expects Sims to be activated from injured reserve in time to play against New Orleans on Sunday. In addition, rookie tailback Peyton Barber continues his steady improvement. When Sims does return, the Bucs may rethink their 46-man game-day active roster a bit, particularly with injuries now starting to hit the receiving corps.

"We've come a long way in a few weeks, from being razor thin, to now having four guys in the backfield – potentially four guys if they're all active – that we trust to give the football to in the running game. And then they all have their different strengths. All those guys can pass-protect. Charles is the best receiver in the group, but none of them are bad. It just gives us more options and then Peyton and Jacquizz have been playing key roles on special teams, as well. Usually on game day, between wide receiver, tight end and running back, you're going to have 12 guys active. We've been kind of going, five, four and three, wide-outs, tight ends and running backs. But based on injures, that may get juggled around a little bit."