CHIBA, Japan -- It turns out Tiger Woods' left knee has been bothering him for most of 2019.

Woods said Monday that the Aug. 20 procedure on his left knee to repair minor cartilage damage is something he had planned to do sometime last fall.

"It just kind of deteriorated over the year,'' Woods said Monday morning at Accordia Golf Narashino Country Club, site of this week's Zozo Championship, the first ever official PGA Tour event in Japan. "It's one of the reasons we were planning on doing it last year. But I screwed up by winning the Tour Championship [in September 2018], and I thought I could keep it rolling.

"It affected the way my back was feeling and my practice schedule. I've been down this road. That was my fifth [knee] operation. It's been nice to have it moving again and not have it catch and lock up. A lot of wear and tear over the year. It's been stressed out for a very long time, and it was nice having it cleaned up.''

Woods said he is actually ahead of schedule in his recovery, because he had planned to have the procedure a few days following the Tour Championship -- for which he did not qualify. "Instead I had it the week of the Tour Championship,'' he said. "The whole idea was to be ready for this event, the Hero World Challenge and possibly Australia.''

That latter event is the Presidents Cup, for which Woods is the U.S. captain of a team that will take on an International squad led by Ernie Els beginning Dec. 12 at Royal Melbourne.

After winning the Masters in April, Woods figured to be a lock to be on the team or pick himself. But he struggled for most of the summer, with back issues, an oblique problem and now -- as he disclosed -- the knee issue.

Woods would only say that he is still considering himself for the team, and he believes the knee procedure "made it more hopeful that I can do all of the above -- play this week, play Hero and play Australia.

"The way I was feeling toward the middle part of the year, it was going to be a tall order to do it all. I was struggling waking, it affected my back, reading putts. I'm excited about having this end-of-the-year run. Feeling much more fit. I don't have the achiness I had the last couple of years.''

Woods will make his four at-large selections on Nov. 7. Among other players he will likely consider other than himself are Tony Finau, Gary Woodland, Patrick Reed, Rickie Fowler, Kevin Kisner and Kevin Na. Woods said he is leaning on the eight players who made the team -- Brooks Koepka, Dustin Johnson, Justin Thomas, Xander Schauffele, Bryson DeChambeau, Webb Simpson and Patrick Cantlay -- to help with the decision.

Where Woods' game is at remains a mystery. The Challenge: Japan Skins, to be played Monday afternoon at Narashino, was to offer one clue. In a made-for-TV skins competition, Woods was scheduled to compete over 18 holes against Rory McIlroy, Jason Day and Hideki Matsuyama.

Woods, 43, has not played since tying for 37th at the BMW Championship at Medinah on Aug. 18. It was his 12th event of the year on the PGA Tour. He arrived in Japan on Friday, hit balls at Narashino on Saturday and then conducted a clinic, among other activities, at a Nike function in Tokyo on Sunday.

None of the competitors were able to see the course until Monday as it had been closed in the wake of a recent Typhoon in Japan that left the venue saturated.

"I want to be fit and ready for the end of the year,'' Woods said. "Been battling through this year. Nice to get over the hump and start feeling good again and go at it full speed.''