Roy scored eight of his 27 points in overtime, and the Portland Trail Blazers overcame Robinson's career-high 45 points Saturday night to beat New York 120-114.
Robinson and Roy are both Seattle natives who played together collegiately at Washington.
"He played a great game, it was fun to compete against him. Every time we get a chance to play against one another it's always fun," Roy said. "We didn't want him to have a night like he did tonight, but hey, we got the win, so I got the overall bragging rights."
LaMarcus Aldridge also had a big overtime and finished with 22 points and 10 rebounds for the Trail Blazers in their second overtime victory over the Knicks this season. Roy had a triple-double in Portland's 94-88 win on Feb. 1.
Together, those two helped ruin what Robinson said was his best game ever.
"Forty-five pretty much washed away," he said. "For the most part guys competed, played hard and we just didn't get the job done. We took it to overtime but we couldn't make shots. That was the biggest tease. They made some clutch shots down the stretch."
Portland (33-30) surpassed its victory total from last season with its second gritty win in two nights. The Blazers, with longshot playoff hopes in the Western Conference, beat Milwaukee 103-101 Friday on Aldridge's jumper with 2.4 seconds remaining.
"We don't feel like we're out of the playoffs yet," Aldridge said. "Also, I think we're trying to finish this season off good. We know if we don't make the playoffs we still want to finish strong."
Quentin Richardson had 20 points for the Knicks, who were without their top four scorers and lost their sixth straight. Jamal Crawford (bruised right hand) and Eddy Curry (sore right knee) were added to the injury list Saturday, with Zach Randolph (bruised right foot) and Stephon Marbury (left ankle surgery) already scheduled to be out.
The Knicks almost overcame that behind Robinson, who electrified a sellout crowd of 19,763 by shooting 16-of-28 from the floor and adding six assists and six rebounds in 52 minutes.
"I thought he was great. I thought our team fought hard and we were very undermanned tonight," Knicks coach Isiah Thomas said. "I can't complain about anything that our guys didn't do because the fact we were even in the game tonight with the way that we had to play and the things that we had to do. I admire the guys in the locker room."
Still, the loss dropped New York to 22-60, the equivalent of a full NBA season, since Madison Square Garden chairman James Dolan gave Thomas a multiyear contract extension on March 12, 2007.
Steve Blake had 15 points and 10 assists for the Blazers, and Martell Webster also scored 15 points. Fred Jones, traded to New York from Portland on draft night, scored 17 points and David Lee finished with 14 points and 14 rebounds.
The Blazers led by three after Jarrett Jack's free throws with 14 seconds left in regulation, but Robinson quickly answered with a layup. James Jones made only one free throw with 8.1 to go, and the 5-foot-9 Robinson rushed upcourt, taking it directly at 7-1 Joel Przybilla to make the tying layup with 2.3 seconds remaining.
But Roy hit two jumpers in the first 1½ minutes of overtime and Aldridge had the next two buckets to open a seven-point lead. Robinson may have finally run out of gas, going just 1-of-3 in the extra period, and the rest of the Knicks were only 1-of-5.
"When a guy like that is scoring, the other four guys are watching," Portland coach Nate McMillan said. "And I thought down the stretch he missed a free throw, he missed some shots that he was making and maybe he was just a little fatigued."
Portland shot 65 percent and led by 12 after a 36-point first quarter, its best opening period of the season. The Knicks cut it to 56-51 at halftime, then pulled to 88-84 after three, with Robinson capping his 22-point quarter by hitting a jumper with 3 seconds left.
Curry revealed after the game he was hurt in the first half of Friday's loss to Detroit and will get tests Sunday instead of traveling with the Knicks to Dallas. "When I woke up this morning, there was a lot of discomfort," Curry said. "It was swollen and it just wasn't right." ... The Knicks lost all four games at Madison Square Garden this week, including their first set of home games on back-to-back nights since December 2003.