Barring a dramatic reversal of fortune, the Celtics’ Doc Rivers will likely become the first coaching casualty of the season. The Celtics are mired in a slump, having won only once going into last night’s action. And this follows a disappointing 33–49 season.

What’s worse is how the Celts are losing: They appear to be a rudderless team and Rivers’s ever-changing rotations have made Larry Brown’s tenure with the Knicks look like an island of stability. However, the problem goes deeper than Rivers, a nice, articulate man ill suited for coaching in the NBA. The Celtics should can the team’s president, Danny Ainge, along with Rivers. Boston’s roster is poorly constructed and its implementation lacks any kind of logic.

Celtic apologists are likely to point at the Celtics’ margin of defeat, which hasn’t been terrible. They have a point; only one of their losses has been by double digits — a 101–88 loss to Detroit in the second game of the season — but it’s worth considering the other numbers. Going into last night’s game, the Celtics were 25th in Offensive Efficiency, points per 100 possessions at 101.9 and 20th in Defensive Efficiency at 107.9. This isn’t merely a quirk of small sample size — last season the Celts finished 19th in both Offensive and Defensive Efficiency.

The Celtics have a reasonably talented group of young players, plus Paul Pierce (one of the best players in the NBA), but the rotation patterns have been inconsistent. So far this year, a former end-of-the-Net bench guy, Brian Scalabrine, has received more minutes a game than Gerald Green, who is widely touted as the next Tracy McGrady.

You’d like to think that if a team was struggling and had the next T-Mac in uniform, they’d try and find minutes for him.

Additionally, the better of the two young Boston point guards, Rajan Rondo, took a Did Not Play–Coach’s Decision against Charlotte last week, and Leon Powe, the power forward who was the surprise of preseason, has rarely gotten into action despite injuries to the starter, Al Jefferson.

Of course, it’s perfectly reasonable to wonder why Rivers is coaching at all. He seems like a class act, but nothing in his track record screams “future Phil Jackson” or even “future Mike Dunleavy.” In seven seasons, his teams have never won more than 45 games, and it isn’t as if he’s been handed a roster of castoffs and told to play in the Western Conference. Instead, his teams have always boasted future Hall of Famers and played in the weakest or second weakest division in the NBA. Furthermore, his teams have never played tough defense, a hallmark of a good coach, and his track record of developing young talent is spotty.

Many observers believe Rivers will be shown the door by Christmas and the Celts would do well to send Ainge with him. I liked Ainge’s approach when he took over three years ago; he wanted the team to get younger and more athletic. And it wasn’t just buzzword dropping — he walked the walk. The Celtics amassed an impressive array of young talent like Jefferson, Green, Rondo, Tony Allen, Delonte West, and Kendrick Perkins. But to create a winner you have to do more than load up on young talent and Ainge failed badly in structuring their development. His track record in trades is also poor. He’s traded forward Antoine Walker, an impact player, twice without much to show for the exchange. More important, it seems he has turned his back on the original program. This summer’s lengthy attempt to trade for Allen Iverson suggests that the team has gotten desperate to build excitement rather than build a winner.

Although he is one of the best guards in the game, Iverson is 31, and backcourt players of that vintage usually aren’t far from the NBA equivalent of AARP membership. Instead of opening the window for championship contention, Ainge began to close it, and save for one first round exit, the team hadn’t really contended yet. Other Ainge moves are also mystifying. The trade this summer of the Celts’ lottery pick for Sebastian Telfair was profoundly lopsided. Telfair had lost his starting job in Portland and no matter how highly you think of the guy’s upside, you don’t trade a lottery pick for someone else’s reserve. The trade left the C’s with an overload of backcourt players and one frontcourt injury from a second straight trip to the lottery.

Unlike the Knicks, where any new executive will have to wait until the contracts of Stephon Marbury and Steve Francis expire in 2009 to make any real impact, a new GM with the Celtics would have the opportunity to make a splash immediately. The roster, though small, is loaded with talent and its cap situation is favorable. The Celtics’ youth movement was the right idea but Ainge got to the rim with it and failed to finish. The right coach and the right GM could get this team turned around fast and make them a powerhouse in the Atlantic for years to come.

mjohnson@nysun.com