Tiger Woods is in contention at The Open and 5 other things we learned from Carnoustie

The first round of The 147th Open Championship at Carnoustie is in the books and Tiger Woods had his best start at a major in four years. Here's more on Tiger and five other things we learned from Thursday's round at Carnoustie.

Americans, South Africans fill top of the leaderboard

The top seven golfers on The Open's leaderboard are from the U.S. or South Africa. Kevin Kisner shot a 5-under 66 to take a one-stroke lead into Friday over South African golfers Erik Van Rooyen and Zander Lombard and American Tony Finau.

After bogeying the par-4 5th hole, Kisner eagled the 6th hole, then birdied four of the next nine holes. Kisner's putting was the story of his round as he putted a round-low 22 times – three fewer than the next lowest total.

"The golf course is great for me," Kisner said. "The conditions have been fine. Going forward, you never know what you're going to have in Scotland. I know the rain is coming in tomorrow. I don't think the rain is going to affect how the golf course is playing in one day, but I have to just keep doing what I'm doing.

"If I have 22 putts the next three days, I bet I'll have a pretty good shot."

MORE: The Open leaderboard | Round 1 photos

Brandon Stone, Ryan Moore and Brendan Steele are in a three-way tie for fifth at 3-under.

Learn more about South African contenders Van Rooyen, Lombard and Stone here.

Tiger Woods is in contention

Tiger Woods shot his first par-or-better opening round at a major since 2014, finishing at even on Thursday and five strokes behind Kisner.

A five-stroke lead with 54 holes remaining is far from insurmountable. Henrik Stenson won The Open at Royal Troon in 2016 after entering Friday five strokes off the lead, as did Padraig Harrington in 2008 and Todd Hamilton in 2004.

MORE: Tiger's history at Carnoustie

"I played better than what the score indicates," Tiger told the media after his round, "because I had two 8 irons into both par 5s today, and I end up with par on both of those. If I just clean up those two holes and play them the way I'm supposed to play them with 8 iron in my hand, I think I'd probably have the best round in the afternoon wave."

Tiger birdied the 1st and 4th holes, prompting golf fans' imaginations to go wild, before he bogeyed three holes on the back nine. He hit 73 percent of the fairways in the first round, which was tied for fifth, and his five scrambles was one of the better marks among The Open field.

Mixed results for the world's best players

Dustin Johnson, the world's No. 1 golfer, is tied for 129th at 5-over after the first round, and half of the top-10 players in the Official World Golf Rankings are over par after Thursday. Justin Rose, Brooks Koepka, Jordan Spieth and Tommy Fleetwood are each 1-over, while Jason Day is even.

Rory McIlroy (-2), Justin Thomas (-2), Jon Rahm (-2) and Rickie Fowler (-1) are among the 31 players who are under par after the first round. None of the top seven golfers on the leaderboard are ranked in the top 30 of the OWGR.

McIlroy told the media that playing aggressive can be a high-risk, high-reward strategy for him at Carnoustie, but it's one worth pursuing.

"Even if you play aggressive around here, you might make more bogeys than playing it safe, but you're going to make more birdies as well," he said. "You're going to give yourself more birdie looks ... I think that's what I have to do. That's my game plan this week.

"I'm convinced that that's the way that I should play it. It's not going to be for everyone, but it worked out pretty well today."

Brooks Koepka salvaged his round to finish 1-over

After birdieing the par-4 1st hole, the two-time U.S. Open champion's front nine went about as poorly as it could. He shot a 5-over 41 on the front nine after closing with double bogey/par/bogey/double bogey/bogey over the final five holes.

But Koepka played like an entirely different golfer on the back nine, shooting four birdies in the first five holes. He finished the round at 1-over, good for tied for 53rd place.

After finishing tied for sixth at The Open last year, Koepka's start on Thursday put him in danger of missing the cut, but he was able to dig himself out of the hole he had put himself in. He missed a birdie putt on the 18th hole that would have given him a 30 for the back nine, but he still finished with six birdies – the second-most of any golfer on Thursday.

Sergio Garcia returns to Carnoustie after losing The Open in a playoff in '07

In his first round at The Open at Carnoustie since The 136th Open Championship when he missed a par putt on the 72nd hole that would have won him his first major, Sergio Garcia shot a 4-over 75 on Thursday. Sergio's opening-round scores at Carnoustie have ranged from 89 (1999) to 65 (2007), and this year he nearly split the difference.

While his 367-yard average on his drives ranked fifth on Thursday, he hit only 47 percent of the fairways and 56 percent of greens in regulation. Sergio's bogeys early on both the front and back nine – the 1st, 3rd, 10th, 11th and 12th holes – were the story of his round as his six bogeys were only offset by two birdies.

Amateur Sam Locke is Scotland's best hope for a native countryman to win

There are five Scottish golfers in The Open field and amateur Sam Locke has the lowest score after Thursday at 1-over. Locke is also tied with Nicolai Hojgaard for low amateur.

He never quite found his groove in the first round, going bogey/birdie/bogey/birdie/bogey on the 5th through 9th holes, then birdie/bogey/birdie/bogey/bogey on holes No. 12 through No. 16.

The other Scottish golfers at The Open include Russell Knox (+2), Sandy Lyle (+4), Scott Jamieson (+4) and Grant Forrest (+9).