After a day of difficult scoring at East Lake, a pair of familiar names are near the top of the leaderboard. Here's how things stand after the first round of the Tour Championship, where Dustin Johnson shares the lead in search of his second straight win:
What it means: Birdies were hard to come by for the 30-man field in the early going, but eventually some of the top players in the world got it into red figures. That group included Spieth and McIlroy, both of whom rebounded from difficult front nines, while Johnson showed that he didn't accumulate any rust in the bye week that followed his record-setting victory at the BMW Championship.
Round of the day: Johnson played in the anchor pairing alongside Patrick Reed, and he may have a similar tee time for the rest of the week after opening with a 4-under 66. Johnson birdied three of his first six holes to grab a spot on the early leaderboard, dropped his only shot of the day on No. 13 and grabbed a share of the lead with a two-putt birdie on the par-5 closing hole.
Best of the rest: Matsuyama defeated Rickie Fowler in a playoff this year in Phoenix, and his perpetually strong ball-striking was complemented by some strong putting during an opening-round 66. Matsuyama birdied four of his first six holes on the difficult outward half, made the turn in 4-under 31 and added two more birdies on the back nine without dropping a shot.
Biggest disappointment: Phil Mickelson shot himself out of the tournament with a 4-over 74, but the concerns for Lefty extend beyond this week. Mickelson missed his first 12 fairways in a row before finding his lone fairway of the day on No. 17. It was a surprising display of inaccuracy from the five-time major champ, who will need to get things back on track in a hurry before heading to Hazeltine for the Ryder Cup.
Main storyline heading into Friday: There is no shortage of star power within two shots of the early lead, but the player to watch remains Johnson. Already the leader for Player of the Year honors entering the week, he barely seemed to break a sweat during the opening round and could be on his way to duplicating-Billy Horschel's double-dip that yielded the FedEx Cup in 2014.
Shot of the day: Kim entered this week as the Tour leader in hole-outs, and he added to that total with a chip-in birdie on No. 18 to close out his round. A winner last month in Greensboro, Kim was recently re-classified as a rookie and could steal Rookie of the Year honors from Emiliano Grillo with a strong performance this week.
Quote of the day: "I was joking with my caddie that this sort of golf would be pretty good next week at the Ryder Cup. Make seven birdies, and you're going to do OK." -McIlroy, whose colorful scorecard included seven birdies, two doubles and a bogey.