Howard, who suffered a knee sprain in the series opener, said Saturday that the throbbing pain has subsided after just over 24 hours of icing and using an Electronic Muscle Stimulator.
"I feel a lot better, really happy about that," Howard said after Saturday's shootaround. "I didn't want it to continue to linger throughout the whole playoffs. So it's good some of the pain has gone away."
Howard suffered a Grade 1 sprain of his left knee in the first quarter of Game 1 and left the game for good less than a minute into the fourth quarter.
Howard was questionable for Game 2 on Thursday and after a 15-minute pregame warmup, he played 40 minutes, scoring 19 points and grabbing 17 rebounds.
Howard missed a career-high 41 regular-season games to various injuries. He missed nearly two months after dealing with swelling in his right knee.
But he's been relatively healthy in the postseason and is leading the league with 14 rebounds per game in the playoffs. He's also been averaging 16.6 points and 2.3 blocks through 14 postseason games.
"It gives us our confidence," James Harden said of having Howard in the lineup. "The confidence that our big fella is back there to protect us. He's going to fight his way through the series. You get that mindset and everybody carries it on the court and you just go out there and compete with the effort."
The Rockets are down 2-0 in the best-of-seven series.