After nearly three months on the sidelines, world No. 1 Brooks Koepka is ready to get back to work.

Koepka headlines the field this week at the Abu Dhabi HSBC Championship, where he'll again attempt to return from a left knee injury that has plagued him since March. After undergoing stem cell treatment following the Tour Championship, Koepka returned in October only to re-injure his patella tendon while slipping on concrete at the CJ Cup in South Korea.

"In Korea I re-tore it, and the kneecap had moved into the fat pad," Koepka told reporters Tuesday in Abu Dhabi. "That's excruciating. It's a lot of pain. It's not fun."

The subsequent recovery kept him out of the Presidents Cup, as Koepka didn't start hitting balls again until just before Christmas. While he told reporters that his injured left knee likely won't feel the same as his right one "for a while," he's pleased with the progress he's been able to make.

"It does feel stable, which leaving Korea and all the way up to about a month and a half ago, it felt like it could go either way," Koepka said. "It could go left, out, back, it could go any way. Even when I got the green light, I just didn't know whether it was going to feel right, whether you're going to be the same, how is it going to feel."

2020 Rolex Series begins this week in Abu Dhabi

Koepka will make two starts this month in the Middle East, as he's also playing in the Jan. 30-Feb. 2 Saudi International. He'll make his first start in the U.S. at the Genesis Invitational.

With Rory McIlroy, Jon Rahm and Justin Thomas all picking up wins since his last competitive start, Koepka, who also missed significant time in 2018 (including the Masters) with a wrist injury, is eager to return to action this week with an eye on a healthier 2020.

"When you have something taken away from you, I think it makes you appreciate it more," he said. "I mean, I missed competition. I missed showing up to an event, preparing for something, because I haven't had anything to prepare for. Having three months off, it's not fun."