World number one Andre Agassi also progressed, charging past Armenia's Sargis Sargsian 6-3, 6-2 in 58 minutes to take his career record to 6-0 against his regular practice partner.
Rusedski let rip with a string of expletives as he questioned the umpire's decision during their second-round match at Wimbledon but there were no verbal fireworks this time -- only power tennis from two of the game's hardest hitters.
Roddick saved three break points in the opening game of the match and broke Rusedski in the next game for the only service break of the night.
"I think the first two games of the match were quite important," Rusedski told reporters. "Had I broken him to start the match, it probably would have been a different story.
"But he's the one who broke me and it set the tone for the first set. The difference in the match was just one or two points here and there -- that's tennis."
In the second set tie break, Roddick led 4-3 on serve when he thumped a backhand passing shot that left his opponent motionless at the net. The American went on to claim the tie break 7-4 to close out the match.
"He played very well in the service games in the second set," said Roddick, who blasted 12 aces in the match to Rusedski's nine.
GOOD PASS
"He picked up a lot of my best returns. I was just lucky enough to hit a good backhand pass in the (tie) breaker."
Rusedski was 5-2 up in the third set at Wimbledon when he believed the umpire should have replayed a point after a spectator called a ball out. Roddick ultimately won the point and, after the Briton's meltdown, the match 7-6, 7-6, 7-5.
"Tonight was just me playing Greg another time," said Roddick, who is ranked sixth in the world.
"Wimbledon is far out of my mind. He blew up and it was an incident but I like to think at two sets up I was going to win that match anyway."
Top seed Agassi, gunning for his sixth Washington title, opened the second set by breaking Sargsian to love to essentially seal his opponent's fate.
"The second set I told myself, 'Make sure you get off to a good start, make sure you execute'," said Agassi.
"I came up with a couple of good returns and controlled the rallies. Getting off to a quick break definitely helps you to loosen up."
Agassi now plays the winner of Thursday night's late match between defending champion James Blake of the United States and Germany's Lars Burgsmuller.
In other matches, American Mardy Fish, the 11th seed, stunned fifth-seeded Yevgeny Kafelnikov of Russia 6-4, 3-6, 6-3 and third seed Paradorn Srichaphan of Thailand beat American Brian Vahaly 7-6, 6-4.
Chile's Fernando Gonzalez, the fourth seed, knocked out Mario Ancic of Croatia 7-5, 7-6.