Mikumu Horikawa is one shot off the pace at the ZOZO Championship, while 2021 Masters champion Hideki Matsuyama struggled in his opening round.
The American made a clutch birdie on No. 17 to take a two-stroke lead to the final hole at the Accordia Golf Narashino Country Club.
The American, who has roots in Japan, was steady throughout and came up big on the final hole.