"It goes beyond the baseball side of things with us," O'Sullivan said. "I have a best friend that I'm close and intimate with, and our families are close."
When O'Sullivan coached at Virginia from 1996-1997, he went up against Clemson and gained respect for head coach Jack Leggett and Corbin, who was on the Tigers coaching staff. O'Sullivan met Corbin during the 1996 season when the two teams played. They maintained contact throughout the season, and when there was a coaching vacancy at Clemson, Corbin and Leggett knew the coach they wanted to go after.
"I was as surprised as anybody when Jack called me, but I think Tim had something to do with that," O'Sullivan said with a grin.
It wasn't much of a decision for O'Sullivan to make the move to Clemson. From day one in the baseball offices, it was evident that the chemistry on the staff wouldn't be an issue. Leggett had his own office that he spent most of the time in, but O'Sullivan and Corbin split one.
It was that office where their bond developed. There were late-night celebrations after big wins and all night film sessions after losses. The emotions they felt together in that office is what brought them close together.
"When you're with someone day in and day out, going through the ups and downs of the season, your relationship is going to grow," O'Sullivan said.
Leggett watched as his two assistants grew closer. Corbin threw O'Sullivan's name into the mix when the Tigers were searching for a new assistant because of the relationship the two maintained during the year. Under Leggett's leadership, the duo became two of the most highly respected young assistants in college baseball.
"The chemistry is important, and we could tell that it wasn't hard for our staff to create," Leggett said. "Our families are close friends off the field, too, and that relationship keeps going."
The group made their first trip to the College World Series as a staff in 2000. The team reached the No. 1 spot in multiple polls and won its first game in Omaha before losing two straight and having their season ended.
In 2002, the Tigers entered Rosenblatt Stadium as one of the favorites to win a national championship. Senior shortstop Khalil Greene was finishing a decorated college career that saw him hit .480 with 26 home runs and 86 RBI.
That didn't change his relationship with O'Sullivan.
"It has been the same," Corbin said. "Nothing changes. When you have a good friend, it's one of those things where you pick up right where you left off. There isn't a whole lot that needs to be said because you are so close. I love Sully. He's like a brother."
When O'Sullivan was offered the Florida job after the 2007 season, he didn't need to ask the opinion of many people. He knew he would likely accept the job, as he recruited the state hard for Clemson and went to high school in Jupiter, Fla. It wasn't a tough choice to take the job, but he still talked to Corbin about it.
O'Sullivan talks about that conversation like it shouldn't be a surprise he went to his best friend for advice. It's rare that a day goes by without the two talking, whether it's about how their teams are playing or how their families are doing.
"We talk a lot about things like that," Corbin said. "We talk about other teams and other situations. We're honest with each other when we share a lot of ideas. We're very honest and can say anything to each other."
This year, O'Sullivan's Gators are making back-to-back trips to Omaha for the first time in school history, while Corbin led the Commodores to the College World Series for the first time in program history. It hasn't changed either's sense of humor, as Corbin joked that he didn't ask O'Sullivan for any advice on being a first-year head coach in the College World Series because he "didn't want (O'Sullivan) to think he was smarter than me."
Those achievements signal the success each has experienced at the programs, but they'll face off Monday night to take control of Bracket One. Florida has won three of the four meetings this season, including the SEC Tournament Championship game.
It's still not a comfortable situation for either head coach.
"I don't enjoy playing Tim," O'Sullivan said at Friday's press conference with Corbin sitting next to him, shaking his head in agreement. "His team will be prepared but you hate to see anyone lose. That's where your heart gets involved. That's one of the reasons I've never called Jack (at Clemson) on scheduling. I don't really have a desire to play him unless the NCAA puts us together."
The NCAA did just that for Monday. The coaches would love to be on opposite sides of the bracket, but the winner Monday will be the favorite for one of the spots in the three-game championship series. Regardless of who wins, it's the relationship between the two that has helped both reach this point in their coaching careers.
"It just goes way beyond baseball for us," O'Sullivan said. "We've played a big role in each other getting to this point."Click here to find out the latest news, notes and rumors about your favorite baseball team.