Amid the celebration during his formal introduction as South Carolina's new coach on Monday, Will Muschamp looked back on what was the worst season for a defense he oversaw.

Muschamp was brought to Auburn to provide an immediate turnaround to an inconsistent defense but his less than one-year stint back on the Plains did not go according to plan. Auburn (6-6, 2-6 SEC) finished the regular season in the bottom four of the SEC defending the run, pass, in total defense, scoring, sacks and third downs.

"I regret that we had a 6-6 season," Muschamp said. "I'm not a big stat guy. I think we made tremendous improvement as the year went and certainly added some very good players to the program."

Though Auburn showed improvement on defense in its final four SEC games, there was still regression from the woes of 2014, which led to Ellis Johnson's firing following the Iron Bowl.

Muschamp's hiring at South Carolina to five-year, $16 million deal comes less than a year into his three-year, $5.1 million deal at Auburn, which had no buyout following the regular season.

South Carolina athletic director Ray Tanner said the lack of buyout was not a factor in his decision to hire Muschamp, whose defenses at Florida, LSU, Texas and during his first stint at Auburn were routinely in the top 10 nationally, over four other coaches he interviewed.

"I don't think that you would question what coach Muschamp brings to the defense of side of the football," Tanner said. "While everybody loves a great offense and running 90 to 100 plays at a time and scoring 48 points, and we would like that too, we also like defense where somebody can stop it when the other team may be on the run. A lot of people can score points today and a lot of people can't stop teams from scoring."

TIMELINE: Will Muschamp's second stint at Auburn

On Nov. 22, Muschamp was adamant he and his agent, Jimmy Sexton, had not been contacted about any other jobs. Less than two weeks later Muschamp said he had multiple options to be a head coach.

"I had some other schools reach out as a possible head-coaching situation that I didn't pursue, quite frankly," he said. "... This certainly was the perfect fit for us."

Auburn coach Gus Malzahn had no regrets in hiring Muschamp.

"Will did a good job for us," Malzahn said. "It just so happened that he got a head job in our league this year that he couldn't turn down."

Muschamp's departure from Auburn, along with defensive backs coach Travaris Robinson and offensive analyst Bobby Bentley, who Malzahn confirmed are no longer with the program, leave the Tigers having to find their third defensive coordinator in as many years, fifth in six years and seventh in the last decade.

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"I hate the fact that those kids have to go through a change again at defensive coordinator," said Muschamp, who called the lack of continuity in scheme a "huge issue" during the season. "That's something that I certainly regret - that they've got to face that. It's very difficult."

Malzahn said there is no timetable for finding Muschamp's successor, who will inherit a defense losing key players at linebacker and in the secondary heading into the 2016 season, which will be a pivotal fourth season for the Tigers coach.

"We got some great kids and they're resilient," Malzahn said. "They're a bunch of good kids."

Man I just feel sorry for the young guys. I've been through 4 defensive coordinators. No player shouldn't have to go through that. — Cassanova McKinzy 30 (@McKinzy30) December 7, 2015

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On Sept 23, Muschamp said, unprompted, that he was "in this for the long haul" at Auburn, but just 74 days later he was gone. On Monday, Muschamp explained why, in light on his three-year contract, which allowed him to walk at no cost at the end of Auburn's regular season, that he spoke of the future.

"I fully expected at that time, given the information I had, that I was going to be and I fully expecting to be," Muschamp told AL.com. "Did you see the house I bought in auburn? I fully expected that. Then this situation arises. Anybody that doesn't understand that, I have no apologies for making the decision what was best for me and my family."

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Muschamp called Malzahn "a first class individual, a great person and an outstanding football coach" and feels "there's a lot of success to be had" for the Auburn defense.

"It's a great situation there and Gus does a fantastic job," Muschamp said. "I'm really hurt we couldn't continue to move forward, but certainly excited about the opportunity here."