Lamar relieved coach Pat Knight of his duties Sunday after a 3-22 record so far this season.
Knight was in his third season with Lamar and had two more seasons left on his contract.
Lamar was 2-11 in the Southland this season and lost by 20 points to Northwestern State Saturday.
"I was told last night to meet with the president and the AD this morning at 10 a.m.,'' Knight said. "I knew it. There's no talk. They said they want to go in a different direction. We struggled for two years. It's all based on the record. It's part of the business.''
Tic Price, a former Lamar assistant, will serve as the interim head coach for the remainder of the season, the school announced.
Knight was 3-28 overall, 1-17 in the Southland last season after an NCAA tournament berth in his first season when Lamar was 23-12, 11-5. Lamar reached the First Four in Dayton that year and lost to Vermont.
Knight replaced his father, Hall of Fame coach Bob Knight, at Texas Tech in the four seasons before being hired by the Cardinals.
Lamar has lost five of six games and has five games remaining in the regular season.
Pat Knight said there was talk of coaching the rest of the season and then being relieved, but he chose to leave now for a clean break.
"I did what I wanted to do,'' he said. "I coached a team in the NIT [at Texas Tech] and I coached a team in the NCAA. I wanted to prove I could do this for my last name. I should have gotten out after the NCAA. But you're sitting there and have a chance to build a team from scratch. You decide to do it and didn't get it done quick enough. So you get fired. That's it. I have no regrets. I'm proud of what I did. I should have done it. You feel loyal to a place after you're fired from a place. We lost eight out of our top 10. We tried it and didn't work.
"I've been around this business. We just didn't win. The bottom line is we didn't win.''
Knight said he spoke with his father Sunday about the dismissal and said it was hard on his father, now an ESPN analyst.
"I just didn't get it done,'' Pat Knight said.