Dustin Johnson tees off the 18th hole during the first round of the Tour Championship golf tournament at East Lake Golf Club in Atlanta, Thursday, Sept. 22, 2016. (AP Photo/David Goldman)
Dustin Johnson tees off the 18th hole during the first round of the Tour Championship golf tournament at East Lake Golf Club in Atlanta, Thursday, Sept. 22, 2016. (AP Photo/David Goldman)

Atlanta — Dustin Johnson was in trouble from the start Thursday, just not for very long. The game feels easy for the U.S. Open champion, who began his bid for the FedEx Cup title on Thursday with a 4-under 66 to share the lead at the Tour Championship.

Johnson had 165 yards from the sand and worried about getting it over the lip of the bunker. He hit 8-iron to 2 feet for birdie and was on his way to his sixth consecutive round at 68 or lower.

Hideki Matsuyama of Japan ran off three straight birdies early in his round and finished with a birdie on the par-5 18th — the nines have been switched at East Lake — for a 66, while Kevin Chappell joined them with a bogey-free round.

Johnson is coming off his third victory of the year at the BMW Championship two weeks ago, and there was no indication that anything has changed. He hit a reasonable amount of fairways (eight out of 14) considering the dry, fast conditions, and only once when he was out of position did he fail to save par.

He is the No. 1 seed in the FedEx Cup, and the top five seeds only have to win the Tour Championship to claim the $10 million FedEx Cup bonus. The top five were all among the dozen players who broke par in the opening round.

Jason Day, the world’s No. 1 player who hasn’t won in four months, dropped his only shot on the opening hole and was at 67, along with Kevin Kisner and Si Woo Kim.

Jordan Spieth didn’t look like he would post anything near a 68 after he was 3 over through two holes. The defending FedEx Cup champion let his short game bail him out in a big way. Spieth holed three straight putts from the 30-foot range — one of them for par — and raced back into the mix on the back nine by holing a bunker shot for birdie right of the 13th green and finishing with a pair of 20-foot birdies.

Rory McIlroy also shot 68. Phil Mickelson had a 74.

At Columbus, Ohio, South Korea’s Whee Kim shot a 6-under 65 to take the first-round lead in the Web.com Tour Finals’ Nationwide Children’s Hospital Championship.

Kim had seven birdies and a bogey on Ohio State’s Scarlet Course in the third of four events that will determine 25 PGA Tour cards. Kim is 35th on the series money list with $9,975 in two events after finishing 127th in the PGA Tour’s FedEx Cup standings.

At Wellesley, Mass., Ellen Port won her third U.S. Senior Women’s Amateur title and seventh USGA championship, beating Andrea Kraus 3 and 2 at Wellesley Country Club.

At St. Louis, Dave Ryan won the U.S. Senior Amateur for his first USGA championship, holding off Matthew Sughrue 2 up at Old Warson Country Club.