Roy helped bring Washington back from an 11-point deficit in the second half and the Huskies beat Illinois 67-64 on Saturday in a second-round NCAA tournament game featuring wild scoring swings.
And just like that, two star guards go in opposite directions.
Roy, the Pac-10 player of the year, is taking the West Coast's Washington (26-6) to the Washington Regional, where it will face the winner of Sunday's game between Kentucky and top-seeded Connecticut.
This will be the second straight trip to the regionals for Washington, which made it last year as a No. 1 seed before losing to Louisville.
Brown and the fourth-seeded Fighting Illini (26-7) go home, coming up short of reaching the regionals for the third straight year. Illinois reached the national championship game last year before losing to North Carolina.
Roy scored 21 points, including five during an 18-7 run that brought the Huskies back from a 53-42 deficit with 12 1/2 minutes to play. Roy scored from inside to tie the game at 60 with 3:27 left, setting up a thrilling finish.
Washington freshman Justin Dentmon - who's from Carbondale, Ill. - scored nine of his 13 points in the late surge, including three free throws in the final 2:20.
Bobby Jones made three free throws in the final 15.5 seconds to give the fifth-seeded Huskies a 67-64 lead. He hit one of two with 12.8 seconds, and Illinois rebounded his miss to set up a final shot. After a timeout, Brown got the ball and tried a long 3-pointer. It missed just before the buzzer and Roy came up with the ball, sparking a wild Washington celebration.
Illinois had an unfathomable start, when it missed 21 of its first 25 shots and fell behind 28-14. Brown couldn't hit from the outside, and the big men were ineffective inside. Coach Bruce Weber tried to exhort his team with his foghorn voice, but even that didn't work.
Then in the span of 3 minutes, 39 seconds, the Illini went from almost desperate to ecstatic. They outscored Washington 19-7 to close the first half. Brown swished a 3-pointer at the buzzer to pull the Illini to 35-33, then celebrated by chest-bumping with Brian Randle in front of the bench.
What Washington coach Lorenzo Romar had feared the most happened - the Illini finally got its inside game going.
Augustine had 10 points during the Illini run, including two three-point plays. Brown scored six points.
The Illini extended its run to 31-9, scoring 12 of the first 14 points of the second half to go up 45-37. Augustine made two shots and McBride hit two 3-pointers.
But Illinois stumbled into another shooting slump and also hurt itself with fouls and turnovers.
Dentmon had a huge four-point play for the Huskies with 4:12 left to close the gap to 60-58. He was knocked down by Jamar Smith just as his 3-pointer went in, and made the free throw.
Neither team scored for nearly a minute, and when one did, it was Washington, with Roy's layup tying it.