Washington ? The game-defining moment came late in the first quarter, when Washington became more than just the Big Three.

Larry Hughes drew a double team and passed to a wide open Etan Thomas, whose two-handed dunk raised the roof and set the tone for things to come.

The Wizards earned their first playoff victory in 17 years Saturday, beating Chicago, 117-99, with a big-man attack notably absent in the first two games of the series.

Thomas scored 20 points on 8-for-9 shooting, grabbed nine rebounds and led a third-quarter spurt that put his team control, supplementing an attack that had come to rely too heavily on Hughes, Gilbert Arenas and Antawn Jamison.

“He was the X-factor,” Chicago guard Ben Gordon said. “He really came in for them today and had an uncharacteristic game. Usually you see Arenas, Jamison or Hughes doing something, but he was very big.”

The victory was the first in the postseason for the Wizards since May 8, 1988, when they beat Detroit 106-103 in Game 4 of a first-round series. Of immediate concern for the Wizards is that they cut the Bulls’ series lead to 2-1, with Game 4 Monday in Washington.

“We were very desperate,” said Brendan Haywood, who added eight points and nine rebounds. “It’s not impossible to come back from 0-3, but it’s definitely very hard. We would have had to pull out our Boston Red Sox tapes.”

The Bulls had taken a 2-0 lead with their own X-factors — Gordon and Andres Nocioni seemed unstoppable in Game 1, and Kirk Hinrich made nearly everything he shot in Game 2 — but the over-the-top hero this time was a Wizards player known as much for his long dreadlocks and his book of poems called “More Than an Athlete.”

Thomas took only five shots and scored nine points in the first two games of the series combined, and his performance nearly tripled his 7.1-point average. He missed the first 32 games of the season because of an abdominal injury.

“We have a special group in the Big Three, and I’m in the supporting cast,” Thomas said. “Tonight, they needed me. I had to be ready just to finish. … We can’t rely on them totally for everything.”