Augusta National reminded us Friday that diamonds are made under pressure. 

The historic course showed its teeth in the second round of the 80th Masters Tournament, with swirling winds and relentlessly firm greens creating treacherous scoring conditions. Only seven players remain under par entering Saturday’s third round.

But the end result to 36 holes was a doozy – Jordan Spieth and Rory McIlroy, two of the game’s great young stars and the second and third ranked players in the world, sitting in first and second place and playing together in Saturday’s final pairing. Spieth enters the third round at 4-under, one shot ahead of McIlroy, who shot a 1-under 71 Friday.

“I’d rather be playing with someone less threatening, to be honest,” a smiling Spieth said Friday. “(McIlroy’s) certainly proven himself in majors.”

For Spieth, Friday was his worst round ever at Augusta National, a 2-over 74, yet he remains solely atop the leaderboard for the sixth consecutive round, a first in Masters history. He led every round in winning the 2015 Masters, tying a course record at 18-under. A year later, a very different, harder type of tournament is unfolding.

“This is nowhere near the kind of feeling of last year,” said Spieth, who held a four shot lead at the same point a year ago.

“Last year, I felt like you still need to make birdies on the weekend. I like this better ... something like a couple under par over the weekend may be good enough (to win), and I feel like I can handle that even better ... This has now gone to very much a U.S. Open-style of play, only more challenging greens.”

Spieth was more animated than usual throughout his round Friday, regularly talking and motioning as the ball sailed into the whipping breeze.

“Boy, that golf course changed very much throughout the day ... I had 4-iron into No. 1 and landed it on the top tier and stuck it. And then 9-irons were pounding over greens by the end of the day,” said Spieth, who tees off with McIlroy at 2:50 p.m. Saturday. “It was very tough to stay cool. I mean, it’s a lot easier said than done. You could say, looks like you got emotional out there. I mean, you guys try it. That was a hard golf course.”

The Spieth-McIlroy showdown has been long anticipated but has never materialized this deep into a major, and both said they were more focused on their own game and surviving the Augusta course rather than feeding into a potential golf rivalry. Spieth is 22 and McIlroy is 26, and both have won multiple major championships. But with Spieth falling back to the pack Friday, a total of 22 players are within five shots of the lead.

“There’s the potential for someone to shoot a few under and move up into the lead from outside the top 25 ... with what I saw on the last six holes (Friday). So I don’t I think either one of us is focused on each other. We’re focused on the course,” Spieth said.

Spieth. McIlroy. Augusta National.

The weekend is here.