Ohio State's Thad Matta and Arizona's Sean Miller coached together at Miami, Ohio and Xavier.
On Thursday, the good friends will square off in the NCAA West Regional semifinal at Staples Center.
"I wouldn't be here today without him," Miller said.
In 2007, Matta's Ohio State team came back to defeat Miller's Xavier team, 78-71, in an NCAA tournament second-round game.
Ohio State went on to advance to the championship game, where it lost to Florida.
"It worked out real well for one of us," Miller said, "and not very well for me."
Matta recalled the night Miller called him as he was trying to decide whether to leave Xavier and accept an offer from Arizona.
Four years later, they will meet again.
"When you do this long enough," Matta said, "your paths are going to cross."