Ireland's Shane Lowry and Rory McIlroy are both in the mix for Olympic medals after superb second rounds in Tokyo.
McIlroy and Lowry were in a tie for seventh with multiple players still on the course when play was abandoned for the day due to a late threat of lightning.
Former Open champion Lowry shot seven birdies and just a single bogey on his way to a 65 at the Kasumigaseki Country Club.
Four-time major winner McIlroy hit a five-under 66 that featured an eagle, five birdies and two bogeys.
Xander Schauffele shot a sparkling eight-under 63 as he put the United States in the gold medal position before the second round was abandoned.
"It felt good, it didn't feel much different to yesterday," said McIlroy, who opened with a round of 69.
"I felt like I played well yesterday, I just didn't score as good as I could have and I think that’s why I came off the course maybe not as disappointed as I would have been because I knew that the good golf was in there and it was nice to see some of that good golf today."
Ranked 13th in the Official World Golf Rankings, McIlroy drove the green on the 294-yard par 4 6th, before sending his eagle attempt 15 feet by.
Holing the return effort, it was the start of a nice run which saw him make the turn on 6-under par.
"It was a momentum starter, I three-putted that green yesterday so I was sort of thinking of that as well," he laughed.
"It was nice to hole that one coming back and it certainly gave me some momentum going to the 7th, that tee shot there was good and the eagle on the 8th was great. There are a few holes here that the length off the tee is an advantage and that is one of them."
Offaly man Lowry reflected afterwards: "Golf's a funny game. I started off lovely and just sort of had that momentum for the whole day then.
"Especially when I came out after the delay. I holed a lovely putt on 13, an eight or nine-footer, and then from there, I just played lovely for the rest of the day.
"I actually missed a short one on 17, which would have been nice to hole, but I’m happy with my score and very happy that I have a chance to do something special over the weekend."
Schauffele is sharing the Games experience with his swing coach father Stefan, whose dreams of representing Germany in Olympic track and field were dashed nearly 40 years ago when he lost an eye in a car crash.
The 27-year-old Californian made his father proud as he roared home with three consecutive birdies, rolling in a 13-foot putt on the 18th at Kasumigaseki Country Club to pip Mexico's Carlos Ortiz for the outright lead with an 11-under total of 131.
Moments after Schauffele's putt, play was suspended and then abandoned for the day, leaving the rest of his group and five others still to complete their rounds.
It was the third such disruption for the tournament and the second for the day, with play suspended for more than two hours just before midday.
