The LSU Board of Supervisors approved a three-year contract extension for baseball coach Paul Mainieri on Friday, keeping him under contract through the 2017 season.

Mainieri, the second-winningest coach in LSU history and a three-time National Coach of the Year, led the Tigers to the 2009 national championship, and the Tigers fell one victory short of a trip to the College World Series last season after winning the Southeastern Conference regular-season title. They finished 47-18 and 19-11 in the SEC.

Although a 2-1 series loss to Stony Brook in a super regional at Alex Box Stadium in June brought the season to a disappointing end, the conference title and near trip to the CWS was a significant improvement over 2011, when LSU (36-20) didn’t reach the NCAA Tournament or even qualify for the SEC tourney.

Mainieri said he and athletic director Joe Alleva agreed to the extension, which does not include a raise, this summer.

“I’m very proud to be the baseball coach at LSU,” Mainieri said in a statement. “I love the fans and the passion they have for college baseball and specifically for their Tigers. I’ve had wonderful kids to coach here and great assistant coaches to work with. It’s a dream come true. I’ve loved every second here, and I’m proud of the program we run and hope to continue to put a team out there that everyone can be proud of, and I hope to complete my career here.”

Mainieri, 55, has a 258-122-2 record in six seasons at LSU, ranking behind only Skip Bertman (870 from 1984-2001) in baseball wins at the school.

“Coach Mainieri’s program excels in each of the areas that we emphasize at LSU — competition, classroom and community,” Alleva said in a statement. “His teams compete for championships every year, the players enjoy academic success and they are active participants in public service endeavors. This extension rewards Coach Mainieri for running our baseball program the right way.”

Mainieri’s extension came nine days after Alleva and football coach Les Miles agreed on a new seven-year deal that included a raise. That agreement came shortly after Arkansas approached Miles about its coaching vacancy, though Alleva said the new deal was already in the works.

Mainieri led the Tigers to the 2009 national championship in his third season. LSU finished 56-17 overall and had a 10-1 record in the NCAA Tournament, defeating Texas in the CWS finals to win its first national title since 2000.

Under Mainieri’s guidance, the Tigers have made two CWS appearances and won three NCAA Regional titles, two SEC championships, three SEC Tournament titles and three SEC Western Division titles.

Last year’s team received a No. 7 seed in the NCAA Tournament. The Tigers won the Baton Rouge Regional and the first game of the super regional before losing two straight.

Mainieri said he and Alleva met a few weeks after the season ended to discuss the status of the program, and that’s when they worked out the extension. Mainieri said he appreciated Alleva recognizing the need to extend his contract beyond the two years that remained to help recruiting.

“It was really an outstanding season up until the last game,” Mainieri said. “You try to evaluate the season overall and not evaluate it just on one disappointing day. I’m very grateful that Joe extended it back to a five-year deal.”