Lin was injured in the first half of the 105-102 loss on Wednesday night and didn't return in the second half. He was trying to chase down a loose ball with Oklahoma City's Thabo Sefolosha.
He underwent an MRI on Thursday that didn't reveal any damage beyond the bruised right chest muscle.
Lin said the main problem Wednesday night was that he was having spasms in the injured muscle. He no longer was experiencing those on Thursday.
"I'm really thankful for that," he said. "So now it's just getting range of motion and being pain free."
The Rockets host Game 3 on Saturday night down 2-0 in the Western Conference first-round series. He wasn't sure Thursday if he'd be ready for that game.
"I'm not going to make any promises or anything because I just don't know," he said. "We'll see how it feels every day and tomorrow we'll re-evaluate it."
When asked if he was more concerned about the injury than he was on Wednesday night, Lin joked about how he repeatedly said he would end up staying with the Knicks before eventually signing with the Rockets.
"No, I'm still hopeful and optimistic," he said. "I just learned my lesson when it comes to making guarantees."
Teammate Chandler Parsons expects Lin to be ready for the game.
"I don't see Jeremy not playing," he said. "He's a tough kid and he obviously wants to play."
Lin said he was using a variety of different treatments in his recovery and that he's trying to remain positive about returning by Saturday.