When the team president of the Knicks, Donnie Walsh, took over a few weeks ago, his first major move — relieving Isiah Thomas of his duties as coach — was obvious and was met with universal joy by Knicks fans. His second major move — agreeing to sign coach Mike D’Antoni — is an even bigger splash. But it hasn’t met with the level of acclaim you’d expect from such a coup.

The D’Antoni hiring isn’t completely official (the two sides are working out the details of the four-year, $24 million contract). But barring something completely unexpected, there will be a press conference this week to introduce D’Antoni as the new Knicks coach.

Count me among the many who are very surprised by the move. For one, the Knicks’ roster did not seem like an especially good fit for D’Antoni’s up-tempo style; for another, he was being courted by the Chicago Bulls, whose roster was a near-perfect match. Credit Walsh for swooping in while the Bulls’ brass twiddled their thumbs. D’Antoni was the most successful available coach — in five seasons in Phoenix, he went 253-136 — and now he’s going to work at Madison Square Garden.

After I got over the shock (I was really amazed that Chicago let D’Antoni slip through their fingers), my second thought was — oh no, not again. Three years ago, the Knicks brought in Larry Brown to coach the team, but the roster was ill-suited for his strategies, which resulted in a 23-59 season and a very messy dismissal that summer. Thomas’s tenure as team president was marked by all kinds of personnel acquisitions that could only be considered as conspicuous consumption. Did Walsh suddenly suffer the same affliction?

After mulling it all weekend — hey, it beat thinking deeply about the Boston-Cleveland playoff series — I believe this is a good hire. First of all, this Knicks roster is a bad fit for any competent coach. Second, D’Antoni’s up-tempo style will force them to prioritize the players that most fans would like to see as the part of the future nucleus of the Knicks.

Forwards David Lee, Wilson Chandler, and Renaldo Balkman are all likely to see a major increase in their minutes this autumn. All three run the floor well and excel in the open court. Guard Nate Robinson might as well go shopping to buy a home in the area rather than rent: His speed makes him ideal for D’Antoni’s style. He might have been traded since there are limited uses for a 5-foot-9-inch combo guard, and that’s taking a very optimistic look at his skills. But the Knicks are almost certain to play at one of the league’s fastest tempos next season and Robinson’s ballhandling on the run will be useful. Swingman Jared Jeffries will also be much more useful on an up-tempo team. The 6-foot-10-inch perimeter player has unusual length and is a good defender in zone defenses and in the open court.

Part of Walsh’s efforts to lure D’Antoni was to have him review the roster and offer him a large say in how the roster would be remade. That kind of power spells the end of the Jerome James era in New York. Few players sat at the end of the bench and collected $6 million a year as well as James; his presence was a reminder of the Thomas administration’s complete incompetence when it came to evaluating veteran NBA talent. James will certainly receive a buyout. Stephon Marbury, whom D’Antoni ran out of Phoenix less than a month after he took over as coach, figures to be traded. Marbury is in the final year of a lucrative contract that will earn him $22 million in 2008-09. While his value as a player has diminished, many teams will want him just for his large expiring contract: Players with big expiring deals are often the key to making trades for superstar talent.

The biggest reason I like the D’Antoni hiring has to do with center Eddy Curry and forward Zach Randolph. The new coach is offensive-minded and even if the minutes of both players are reduced, they should still put up good numbers in D’Antoni’s system. This will enhance their trade value, since neither player is a good long-term fit for the Knicks.

Swingman Quentin Richardson is a puzzle to me. Last season was easily his worst as a pro, but Q had one of his best seasons with D’Antoni in Phoenix. I don’t know if D’Antoni knows how to coax a better season out of Richardson, but I’m sure that guard Jamal Crawford could be in for one of his best runs. Crawford is a sharpshooter when left open, but brings his percentage down with bushels of ill-advised, contested long jump shots. In D’Antoni’s system, with a spread offense, plenty of open perimeter shots, and chances to drive to the hoop, he should thrive.

Some of D’Antoni’s critics have noted that in Phoenix, the coach inherited a roster with two top players — forwards Amare Stoudemire and Shawn Marion — and soon after he took over, they signed point guard Steve Nash, who won two Most Valuable Player awards in Phoenix. D’Antoni has worked with a less talented roster, too. His first coaching stint was in 1999, and while his .280 winning percentage wasn’t gaudy, he was taking over one of the worst teams in NBA history: the 11-71 Denver Nuggets of 1997-98. D’Antoni’s season amounted to a 110% improvement. Although a front office change limited his tenure there to one year, D’Antoni turned the Nuggets into an up-tempo team and greatly improved their offense. I expect he’ll do the same here. With the right offseason acquisitions, this team could flirt with .500 next season.

mjohnson@nysun.com