MELBOURNE, Australia -- The No. 1 player in the world early in the year, Dustin Johnson didn't show up on the leaderboard the last three months of the PGA Tour and hasn't been seen at all since then.
Both can be attributed to an ailing knee.
It shouldn't take long to find out how quickly he recovers.
Johnson is part of the opening session Thursday in the Presidents Cup, his first competition since Aug. 25 at the Tour Championship. He finished last in the 30-man field at East Lake, and then had surgery on his left knee to repair cartilage damage.
"Unless I didn't feel like I could come here and help the team, then I wouldn't have come," Johnson said. "But I feel like I definitely can help the team, and the game is in good enough form to where I feel just fine."
Johnson nearly staged the biggest comeback in major championship history at the PGA Championship until Brooks Koepka held him off. Over his next eight events, he never finished better than a tie for 20th.
He didn't want to use the knee as an excuse, though it was hard to overlook. He had eight top 10s this year, his fewest since he missed the last five months of 2014 while trying to get his life back in order.
"I can't ever blame anything. It was me. I just played poorly," he said. "But obviously, it had some kind of an impact on it. Now, I mean I had a lot of time sitting on the couch, just thinking back on the year. I was struggling, and what I was struggling with in my golf swing, you definitely could relate it to the knee with what I was doing, which was hanging back too much and just not controlling the golf ball well enough."
U.S. captain Tiger Woods sent him out in the anchor match of the opening fourballs session, playing with U.S. Open champion Gary Woodland against the International side of Louis Oosthuizen and Adam Scott.
Johnson raised some concerns when he decided at the last minute to withdraw from the Hero World Challenge in the Bahamas, saying he wanted one more week of rest and some practice to make sure he was ready for Royal Melbourne.
Woodland said he expects nothing but the typical game of Johnson, who has held the No. 1 ranking for more weeks than any player over the last five years. With his slump at the end of the PGA Tour season, and being off for the last three months, he now is No. 5.
"DJ looks great," Woodland said. "Not many people outside of Tiger Woods can take that kind of break off and come back and look pretty good. Yesterday, you could maybe say he was a little rusty early in the round, made some birdies late. Today he played great. I expect him to be playing quite a bit this week."
Johnson returned from his six-month hiatus at the end of 2014 by missing the cut at Torrey Pines. He finished among the top six in five of his next six tournaments, including a World Golf Championship title at Doral.
"You could see into the round his speed coming back," Matt Kuchar said. "Same today. Man, he's such a talent. You'd hardly noticed he's had time off for surgery."
Johnson has played all five matches in his last Presidents Cup and Ryder Cup appearances, and he doesn't expect that to change. He remains one of golf's biggest talents. Now it's a matter of how he performs Thursday, and what Woods has in mind for the rest of the week.
Johnson doesn't expect to play all five sessions.
"I'll play as many as Tiger wants me to play," he said. "I wouldn't be here if I wasn't ready to play."
More AP golf: https://apnews.com/apf-Golf and https://twitter.com/AP—Sports