BOSTON — If this week’s mega-deal for Kevin Garnett taught Celtics fans anything, it’s that timing in running a pro sports team is everything.

When Danny Ainge began in the spring trying to land a major talent to pair with Paul Pierce, Garnett was the biggest fish available. At that time, Minnesota’s Big Ticket had his sights set on joining Kobe Bryant in Los Angeles (where he owns a home) or perhaps Steve Nash in Phoenix. Garnett was also given permission by the Timberwolves to speak with Ainge but his plans had nothing to do with coming to the team with the worst record in the Eastern Conference.

No deal with the Lakers or Suns came off, of course. Instead, Minnesota general manager Kevin McHale hung on to Garnett but kept his ears open. When he saw Ainge in Las Vegas at the pro summer league, the two old teammates started talking trade once again. The Celtics had already landed Ray Allen on draft night, but Ainge didn’t have to surrender the two pieces of Boston’s roster he cherished most: young big man Al Jefferson and the $11-million salary cap slot for center Theo Ratliff that expires after the 2007-08 season.

With McHale still interested in the Celtics and Ainge still coveting a top five player such as Garnett, the impetus for the monster deal was still in place.

“Making a trade in the NBA is very difficult,” said Ainge. “We happened to be in the market for a player like KG and [Minnesota] was in a rebuilding mode. We had one of the best young players in the league in Al Jefferson so they decided to go in that direction. All sorts of things had to fall into place.”

While Ainge and McHale lined up the pieces to the deal, the next step was getting Garnett to agree to come to Boston. That process actually began on draft night when the Celts acquired Allen, a longtime Garnett friend and fellow South Carolinian.

“I reached out and spoke to Ray,” said Garnett. “I asked Antoine [Walker] about the city and he had nothing but great things to say about the city. I spoke to GP [Gary Payton] about the city. Slowly but surely I got a lot more comfortable about the situation and was able to visualize myself in a Celtics uniform.”

Garnett has shot down any notion that he had issues with Boston because of race troubles that date back to the 1960s. “You hear things about Boston being racial, but racism exists everywhere. I’m from the South. I’ve experienced racism. Antoine [Walker] said it’s a good place. I’m happy with that.”

With Garnett excited about joining Allen and Pierce in Beantown, Ainge and his number crunchers went to work on a contract extension. Garnett has two years left on his deal with Minnesota and the Celts signed him to a three-year extension. Over the next five years, the team will pay the 6-11 center a reported $105 million. Next year alone, the franchise’s reincarnation of the Big Three will earn a combined $56 million.

The team’s new star power has already made waves. Before the start of the news conference announcing the trade Tuesday, Celtics’ vice president Jeff Twiss jokingly announced that the team’s ticket office was open and ready for business.

Team president Rich Gotham told The Boston Herald that the trade sparked a record-setting response from fans. “We had done $2 million in sales on the first day, and we’ve kept up a similar pace in the days that followed,” he said.

The NBA has noticed, too. After failing to appear on the league’s national TV partners — ABC, ESPN, TNT — a single time last season, the reenergized Celtics will be shown coast-to-coast often in 2007-08. The Celts are scheduled for seven ESPN dates, three on TNT and nine more on NBATV.

kmcnamar@projo.com