Big-time college baseball was a massive adjustment for Tulane sophomore Justin Campbell after a dominant senior year of high school in Michigan, which he ended with a complete-game shutout in the state championship game.

He needed only one season to figure it out, though.

Campbell, a soft-tossing, mustache-wearing lefty with huge movement on all of his pitches, struck out the last five batters in a three-inning save as Tulane beat South Florida 6-4 on Sunday at Turchin Stadium, completing a weekend conference sweep for only the second time in eight opportunities under third-year coach Travis Jewett.

“I wasn’t sure if I was getting more than a batter, and I wasn’t sure if I was getting an inning,” Campbell said. “I just attacked each one as if it was my last. I felt fantastic.”

Campbell wiped away all of that negative history in close-out games, helping the Green Wave reach a milestone with some long-term historical significance.

Tulane (25-11, 7-2 American Athletic Conference) equaled its best start in league action since it started playing full conference schedules in the early 1990s. The other times it happened led to pretty special years, with the 1999 team earning a No. 1 seed in a regional, the 2004 team reaching a super regional and the 2005 team going to the College World Series.

This group is not there yet, but the weekend against cellar-dwelling South Florida (15-19, 2-10) was a good start. The Wave, which has won six in a row, led at the end of all 27 innings and did not commit an error.

“It’s huge,” Jewett said. “Once you do something for the first time, then it becomes something you’ve done before. Hopefully we’ll be able to build off of it.”

Just as pleasing to Jewett was the way Tulane won Sunday. Going without a home run for only the second time in 13 games, the Wave still jumped out to a 5-0 lead while getting five nearly flawless inning from starting pitcher Chase Solesky (4-2). The only hit he allowed to that point was a pop-up that second baseman Jonathon Artigues lost in the sun.

When Solesky imploded in the sixth, giving up five hits as the Bulls closed within 5-4, the bullpen took care of the rest.

Campbell was the stalwart. Pitching for a team-leading 20th time on Sunday — four more than anyone else on the staff — he earned his second save of the weekend. The befuddled South Florida batters struck out six times and had no hits in three innings.

“There was zero chance that he was coming out of the game,” Jewett said. “We can bring him in for matchups, and if he’s cruising, we can elongate him out a little bit. He’s been a nice little silver bullet for us.”

Campbell worked on mixing in a side-arm delivery in practice last season, making it harder to see his other pitches, and perfected it in the offseason. Whatever the reason, his entire arsenal is at a different level than a year ago, when he pitched 1⅓ innings.

“Sometimes you have to look yourself in the mirror and just realize I need to be a better pitcher to get on the mound,” he said. “Then you have to make the effort to do so.”

The only pain the Wave felt belonged to Kody Hoese, the nation’s leader in home runs. After raising his batting average to .409 by doubling and scoring in the first, he was hit by a pitch near the elbow and another in the ribs in his next two plate appearances.

“They both hurt," he said. "The first one made my hand go numb and the next one knocked the wind out of me, but I was fine after that.”

Follow Guerry Smith on Twitter, @guersmith