Presidents Cup: Fit-again Dustin Johnson tells Tiger Woods: I'll play as many times as you want

International team player Cameron Smith admits his friendship with US star Patrick Reed has been damaged after calling him a cheat

Dustin Johnson of the US team plays a shot during a practice session at the Royal Melbourne Golf Club. EPA

Former world No 1 Dustin Johnson says he will "play as many times" as captain Tiger Woods needs him to as the US look to defend the Presidents Cup at Royal Melbourne.

Johnson has not played since the Tour Championship in August and had arthroscopic surgery to repair cartilage damage in September.

The American, 35, said on the eve of the tournament that pits the best of the US against a crack International team that he has fully recovered after his withdrawal from last week's Hero World Challenge in the Bahamas sparked concerns for his fitness for this week's matchplay showdown.

But the big-hitting 2016 US Open champion told reporters Wednesday: "I'll play as many [times] as Tiger wants me to play. I wouldn't be here if I wasn't ready to play.

"I was always planning on playing. The game is in good enough form."

Johnson said he had suffered no setbacks since the surgery, but admitted it had taken longer than expected to find his rhythm.

"I was chipping and putting, three, four weeks after, but I didn't start hitting probably until six to eight weeks, like wedges and just kind of built up from there," he said.

"Everything was right on schedule. If anything, ahead of schedule. The only thing that took longer was with the driver."

Johnson, playing in his fourth Presidents Cup, has not had a top-10 finish since the US PGA Championship in May.

The world No 5 could potentially be asked to play five times over the next four days in the Australian state of Victoria, but US vice-captain Steve Stricker said he had no concerns despite Johnson's long layoff.

"Not at all," Stricker. "He looks great out there.

"He's hitting it a long way as he normally does. His knee is not an issue at all. He's feeling good and hitting it well."

Fellow vice-captain Zach Johnson said his namesake took a few holes to shake off the rust.

"Tuesday, first day out, that kind of thing, everybody kind of had a little bit of fog there early," he said.

"But the last 12 holes, even the guys he was playing with are like, 'Oh, someone's back'. It looked good, especially from a health standpoint."

Australian Cameron Smith has admitted his friendship with US star Patrick Reed has been damaged after calling him a cheat.

Reed was docked two strokes for improving his lie during the Hero World Challenge last week.

Smith responded by telling local media he had no sympathy for "cheats", which sparked a denial from Reed that he had done anything wrong.

The Australian, on Ernie Els' International team, said he had not spoken to Reed since.

"I'm sure he didn't like it. I think there is a little bit of tension there. I've looked at Patrick a couple times but he hasn't looked back," Smith said after a practice round on Wednesday.

Asked if he would try and talk to him to clear the air, Smith replied: "I definitely won't go out of my way. I think our friendship, I guess, is not quite there anymore."

He suggested though that if Els wanted him to break the ice, for the good of the team, he would consider it.

"You know, what Ernie thinks is best I'm willing to do. I'm here to do a job for Ernie and that's all I'm focusing on."

Woods came to Reed's defence on Tuesday, calling him "a great kid" who would not let the row hinder him in the Presidents Cup.

Smith was not picked for the opening fourball round on Thursday while Reed was selected to play alongside Webb Simpson against Hideki Matsuyama and CT Pan.