Mike Woodson admitted he blew it. The Knicks coach said yesterday he could have protected Carmelo Anthony from a nasty spill that KO’d him with a right-knee injury Monday had he only listened to his star’s request to exit the game. Now the gaffe could cost Anthony at least two games. “Melo was hurting,” Woodson said in his weekly appearance on ESPN Radio. “He asked me to come out of the game before he actually took that spill. It made me realize something wasn’t right. He’s never ever, ever wanted to come out of a game. I’ve played him too much. Melo is a trouper, warrior and tough kid.” The Knicks listed Anthony as questionable for tonight’s game at Detroit because of a "stiff/sore right knee." General manager Glen Grunwald, in an appearance on WFAN, said Anthony is “not certain” for tomorrow’s game against the vaunted Thunder at the Garden. “We’re going to try to be smart about it and not rush it along,” Grunwald said. “See how he reacts to treatment. We’ll keep our fingers crossed and hopefully he’s a quick healer, which he has been in the past.” Woodson’s mea culpa occurred the day after the Knicks rallied to beat the Cavaliers after Anthony left the game with the team down 22 points. Anthony checked into the game with 8:57 left in the second quarter and two-plus minutes later he was on his backside, his knee buckling after catching a midcourt feed from Jason Kidd. “I should have [taken him out],” Woodson said. “Stubborn coach. I just didn’t. We’re down 22. I’m going to leave one of my best players in the game. “Maybe I should’ve taken him out before he stumbled and took the fall,’’ Woodson added. “I’m thinking the game, he’ll play through it and figure it out. He was hurt, and walked out after he took the spill and didn’t come back. That’s not Melo-like.” Anthony said his knee has bothered him for two weeks, but the Knicks medical staff has not diagnosed anything serious. Anthony said he underwent an MRI exam Saturday and no structural damage was found. Woodson disputed the suggestion Anthony was motivated to bolt the contest because he was dejected the club was down 22 and he was playing at less than 100 percent. Anthony was 0-for-4 shooting in the first quarter and 1-for-5 when he left, finishing with a season-low six points.