ATLANTA -- Scottie Scheffler has company.

Having entered the day with a seven-shot cushion at the Tour Championship, Scheffler's 36-hole lead is only four strokes after he posted a 5-under-par 66 Friday at East Lake Golf Club.

Collin Morikawa, playing with World No. 1 Scheffler in the final pairing, made nine birdies on his way to an 8-under 63. After the tournament's staggered scoring start handed Scheffler a two-shot edge to start the week, Scheffler now stands at 21 under par and Morikawa at 17 under.

Xander Schauffele re-entered the conversation, as well, with a flawless 64 that boosted him to 16 under. No one else is closer than 12 under, where Sahith Theegala, Wyndham Clark and Australia's Adam Scott are tied.

Scheffler had created space between himself and the field after opening with a 65 Thursday. Schauffele and Morikawa bit back Friday, making the final push for the FedEx Cup more interesting.

"I mean, it's the second round of a tournament. It's the second round," Scheffler said. "I mean, it's a long tournament. Just trying to do my best to stay out there and execute shots, and today I did a pretty good job of that."

There was no 36-hole cut Friday as the top 30 players in the FedEx Cup standings compete for the season-long championship. The winner after 72 holes will take home the FedEx Cup and a $25 million prize.

Scheffler, Morikawa and Schauffele were among eight players left on the course when a lightning delay interrupted the round. After one hour and 33 minutes, the players returned to their marks in the fading daylight.

Scheffler promptly birdied the 16th hole, but Morikawa responded with an 8-foot birdie putt at the 17th after Scheffler's try grazed the cup. They played the par-5 18th hole in exactly the same way, pitching their third shots just a few feet from the hole and tapping out for birdies.

The 28-year-old Scheffler, vying for his first FedEx Cup title, said his seven-shot advantage was the product of some of his competitors not having their best stuff in the first round.

"Then today was a day where I had a ‘big lead,'" Scheffler said, deploying air quotes, "but there was a huge group of guys right there, so obviously some guys are going to play pretty well. But I did a good job of staying in my own world out there and put up a good round of golf."

Morikawa, though, was asked if he enjoyed the chance to play alongside Scheffler after Schauffele was paired with him in Round 1.

"A little bit," Morikawa said. "He's such a good player that you just know he's going to keep going low and making birdies. I saw that firsthand. I've seen it for years. For me, it's just keep my foot on the gas and keep sticking to my game plan."

Both Scheffler and Morikawa birdied the third, sixth and eighth holes, but Morikawa also notched one at the long par-4 seventh after he spun his approach shot inside 3 1/2 feet.

One group ahead, Schauffele went back to work, making up for the 1-under 70 he shot Thursday. The No. 2-ranked player in the world had four birdies on the front nine, including putts from 18 1/2 and 14 1/2 feet.

Schauffele birdied the par-3 11th, yet still trailed by six because Scheffler birdied No. 10 moments later. But Scheffler hit from bunker to bunker at the 13th and couldn't convert a 9-foot par save, and Schauffele made quick work of the 14th hole for his sixth birdie to make it a two-shot swing.

The PGA and Open champion capped off his day with a birdie at No. 18.

"Being two back and then shooting 1 under yesterday and him shooting low round of the day, it's just not the start I needed," Schauffele said. "A sense of urgency today to try and pick some up."

Theegala, a 26-year-old playing in his second Tour Championship, birdied four of his final five holes to rally for a 66. Clark and Scott each shot 67, with Clark's highlight coming on a 15-foot eagle putt at No. 14.

"It's going to be very tough to catch up with (Scheffler)," Clark said. "He'd have to not play his best, and I'd have to play unbelievable."

Sam Burns (68) is alone in seventh at 11 under. Tony Finau shot a 66 early in the day and moved to 9 under, tied with Japan's Hideki Matsuyama (70).

--Adam Zielonka, Field Level Media