Associated Press
Kevin Garnett

WALTHAM, Mass. — When Kevin Garnett starts screaming, the Celtics' defense stops struggling.

For all his assets — athleticism, intensity, intelligence — it's the ability to communicate with teammates that he considers the key to Boston's skill at shutting down opponents.

"I talk. I understand how defense works," he said after being selected the NBA defensive player of the year Tuesday. "Communication's probably the biggest thing when it comes to defense."

An outstanding defender throughout his previous 12 seasons, all with Minnesota, Garnett won the league award for the first time by a wide margin one day before Boston takes a 1-0 lead into Game 2 of the first-round series against Atlanta.

He had 90 of the 124 first-place votes and a total of 493 points. Marcus Camby of Denver, last year's winner, was second with 12 first and 178 points, just edging Shane Battier of Houston, who received 11 first-place votes and 175 points.

"Any award you're able to acquire in this league is a big deal," said Garnett, who would much prefer his first NBA championship. "At the end of the day, it's about winning."

The 6-foot-11, long-armed forward is the major factor behind the Celtics' climb from a mediocre defensive team to perhaps the best in the league. They held opponents to an NBA-low 41.9 field goal percentage after allowing them to hit 46.8 percent of their shots last season. And they allowed just 90.3 points per game, second-fewest in the league, after giving up 99.2 last year.

No surprise, then, that Boston improved from 24-58 last season to 66-16, the NBA's best record, after trading for Garnett last summer.

"He's changed our culture defensively," coach Doc Rivers said. "That's the most important thing, just the team part of it. Individually, he's been fantastic, but I think his presence for the team is what stood out."

He averaged 1.2 blocks, 1.4 steals and 7.3 defensive rebounds to go with 18.8 points and 9.2 total rebounds per game.His decibel level was high, too.

"You have to be able to talk, understand what's about to happen and then, obviously, speak on it," he said, "and talk loudly because sometimes you're on the road and you're dealing with (noisy) crowds."

The crowd will be very noisy Wednesday night, but it will be rooting for the Celtics against the Hawks in the best-of-seven series between the top and bottom seeds in the Eastern Conference.

The defense excelled in Sunday night's opener, a 104-81 win in which Boston held Atlanta to 38.2 percent shooting.