"We were at a point as a team where we were just treading water," McHale said. "The ups and downs, we just couldn't find any consistency."

The Timberwolves looked to be turning the corner at the start of the new year, when they opened 2007 with seven wins in their first eight games.

But they lost their next four games, including one to Phoenix without leading scorers Kevin Garnett and Ricky Davis, who were suspended. Garnett was suspended by the league for a confrontation with Detroit's Antonio McDyess, while Davis was suspended by the team for acting out during Friday night's game with the Pistons.

"It was just basically two steps up the hill and two steps down," McHale said. "We were never able to establish a style of play that we could bank on over and over again."

Casey and his agent did not immediately return messages left by The Associated Press.

Assistant coach Randy Wittman will take over as interim coach in a situation similar to 2005, when longtime coach Flip Saunders was fired in midseason and replaced on the bench by vice president of basketball operations Kevin McHale.

McHale had no designs on taking over permanently, so he turned to Casey, who spent 14 years as an assistant in Seattle, to take over. Casey was just 33-49 in his first season, one made more difficult by an eight-player trade with Boston at midseason that upset the chemistry of a group that had been together for some time.

The Wolves brought Wittman and longtime assistant Bob Ociepka onto Casey's staff for this season, hoping an influx of experience on the bench would help the first-time head coach with his game management.

While the teams has shown some improvement this season, especially in closing out close games, the inconsistencies on both ends of the floor left them 20-20 following Monday night's 106-91 loss at Utah.

That wasn't good enough for Wolves owner Glen Taylor, who wants his team to return to the form that made it a Western Conference finalist in 2004. He also knows that the Timberwolves have to start winning now to placate Garnett, the former MVP who has made it clear on more than one occasion that he is growing tired of the mediocrity.

"We just had these unbelievable swings inside of a week, inside of a game," McHale said. "We were just very eratic."

But Garnett has most frequently directed his ire toward McHale, who has struggled to surround the superstar with enough talent to compete in the powerful West. Garnett has seldom criticized Casey in his tenure here.

McHale traded veteran Sam Cassell and a No. 1 draft pick to the Clippers for Marko Jaric, and sacrificed valuable cap room by spending millions on contracts for Jaric, Troy Hudson and Eddie Griffin, all of whom have not panned out in Minnesota.

Casey and the Timberwolves improved to 20-16 last week after a 94-90 victory at Detroit. But they followed that up with an ugly home loss to Atlanta and a double-overtime loss to the Pistons before starting a five-game road trip with back-to-back blowouts against Phoenix and Utah.

Now it's Wittman's turn. It will be his second try as a head coach, having compiled a 62-102 record in two seasons with Cleveland from 1999-01.

Wittman is plenty familiar with the Timberwolves, having served as an assistant here in three different stints for a total of 10 seasons.

"He knows Kevin, our top player, very, very well," McHale said. "Witt's going to be the coach for the rest of the year. I fully anticipate Randy being here a long time."

Casey's firing means Saunders, who spent almost 10 seasons at the helm, is the only coach in the franchise's 18 years to last more than two seasons.