"I feel great," the 39-year-old center said after the Sharks morning skate. "I've been watching a lot of hockey lately, so to play is going to be fun.
Thornton tore the ACL and MCL in his right knee during a game against the Winnipeg Jets on Jan. 23 and had season-ending surgery two days later. He played the first two games this season but had swelling and soreness in his knee after playing against the Los Angeles Kings on Oct. 5.
Thornton said he has been receiving antibiotics for his infection through a PICC line, but that was removed Monday.
"They were going back and forth if I could play or if I can't," Thornton said of San Jose's medical staff. "Yesterday they just decided to take it out. It was a good day."
Thornton was cleared to play Tuesday morning and activated from injured reserve. To make room, center Dylan Gambrell was sent to San Jose of the American Hockey League.
"I'm still going to be on some antibiotics and stuff like that," he said. "It looks like [the infection] is on its way out, so I get to play, which is nice."
Sharks coach Peter DeBoer said Thornton's blood tests indicate the infection no longer is a problem.
"If he's on antibiotics he's just finishing a cycle, but he's healthy," DeBoer said.
Thornton centered the top line between Joe Pavelski and Timo Meier during the morning skate.
"It's awesome," Pavelski said of Thornton's return. "He's gone through a lot, he really has, over the last little bit. This is another little bump, but he's had the energy, he's had the work ethic. There's nothing that we'd question there, so we're excited to have him back."
The injury to Thornton's right knee came after he tore the ACL and MCL in his left knee April 2, 2017. He returned two weeks later and played the final four games of a six-game loss to the Edmonton Oilers in the Western Conference First Round, then had surgery April 24, 2017.
Thornton has been practicing since Oct. 16 and said he feels strong.
"I'll probably be a little bit tired the first game, but I'll be fine," he said.
Thornton has one assist in two games this season. He ranks 12th in NHL history with 1,031 assists and 16th with 1,428 points. Tuesday will be his 1,496th game, moving him past Phil Housley for 20th in NHL history.
