Hunter Mahan didn't hit his best chip, only this time it didn't cost him.

He was short of the 14th green Friday at the AT&T National, 100 feet from the hole just beyond a steep ridge. His caddie told Mahan if he didn't hit the cup on the way to the hole, it might get a slope on the other side and come back toward the hole. Mahan wanted to chip with just enough pace to get over the ridge and to the hole.

"I hit it a little thin," he said.

It raced beyond the hole, made a U-turn at the back of the green and nearly went in, settling 2 feet away for an easy par. It wasn't quite the way he drew it up.

"I expected to hit it a little bit cleaner off the club face," Mahan said. "But that's how you shoot 65 — get good breaks like that."

That really was the only break Mahan received over two superb days on a demanding course like Congressional. The rest has been pure ball-striking, which has carried Mahan to two wins already this year on the PGA Tour and has him on track for another.

He wound up with a 6-under 65 in the stifling heat — with more hot weather on the way — that not only matched the best score of the day, it gave him a two-shot lead going into the weekend at the AT&T National.

Tiger Woods stayed in the game with a 68 in the morning, when it was still so hot that towels were used to wipe sweaty faces more than to clean clubs. He talked about the value of staying fit and strong to survive days like this. He was five shots behind.

Mahan missed only two fairways and three greens. He has countered only three bogeys with 10 birdies, and he still doesn't know how so many good putts in his opening round stayed out of the hole.

It was such a clinic that despite temperatures topping 100 and a course that feels like a U.S. Open, Mahan made it look easy.

He even used the word "fun" before catching himself.

"I really enjoy playing here," he said. "This is a fun ... this is a great test. I feel like it's not unfair. I think it gives you birdie opportunities. You just have to take advantage."

That he did, reaching 7-under 135, with a game that swing coach Sean Foley recognized Thursday by saying Mahan is "like a laser show right now."

Robert Garrigus had his sixth straight sub-par round at Congressional — that includes last year at the U.S. Open when he became a footnote in history as only the fourth American to break par all rounds of a U.S. Open — with a 67 and was two shots behind, along with Jimmy Walker and Brendon De Jonge, who each had a 69.

Mahan, though, has set himself apart for two days.

"I hit a lot of good shots," said Mahan, who missed only two fairways and three greens. "I hit so many fairways and greens, I made it easy on myself. This is a pretty punishing golf course if you get off line a little bit. I put myself in some great spots to make putts. And I felt like I played well on the back, when it was getting really hot and you're getting a little bit more tired."

Stewart Cink, who draped a towel over his head waiting his turn to putt on the 14th green, showed signs of a resurgence with a 68 that put him in the group three shots behind, along with Vijay Singh (70), Pat Perez (69) and Rod Pampling (67).

More telling than only 18 players who remained under par was the cut at 148. It was one shot higher than the cut for the U.S. Open last year at Congressional, and it was the highest score to make the cut at a regular PGA Tour event since 149 at The Barclays in 2009.

Woods was at 2-under 140, in a tie for 11th. He was as happy about two pars as he was with his 50-foot eagle putt on the 16th hole that put him under par for the first time all week.

He was in trouble early after a few tee shots were caught in the dense rough that makes Congressional feel like a U.S. Open and forced him to hack out short of the green. Both times, he hit wedges that landed by the hole, bounced 15 feet by and caught the slope to come back within 3 feet.

"The pars at 14 and 15 were something I needed to have happen," Woods said. "I hit two good wedge shots in there after two poor drives and gave myself a couple good looks, made those, and then I rewarded all that hard work at the next hole with eagle."

Woods was three shots behind when he finished, and didn't expect to fall back much farther. The course, already looking like it was supposed to play last year for the U.S. Open, was getting firm and crusty from the scorching heat. It was the kind of day reminiscent of when Ken Venturi won the 1964 U.S. Open at Congressional, so dehydrated he almost didn't finish. And high heat was expected well into the weekend, making this a test of survival.

Garrigus took advantage of a forward tee on the 12th hole to stuff his approach inside 4 feet, and then he really let his length work to his advantage toward the end of the back nine. He belted a 348-yard tee shot beyond the bunkers on the par-5 16th that left him only a 6-iron into the green. And on the 18th, with the tees moved up to 481 yards, he hit a drive so far along the downhill fairway that he had only a lob wedge left. He spun that back to a few feet.

He closed out his round on the par-5 ninth, which played 597 yards. He hit 7-wood for his second shot just short of the green to set up an easy birdie.

Garrigus was rightfully proud when he mentioned Thursday evening that he was only the fourth American with four sub-par rounds in the U.S. Open. The others were Lee Trevino at Oak Hill in 1968, Lee Janzen at Baltusrol in 1993 and Curtis Strange at Oakmont in 1994. Strange and Garrigus are the only ones in that group who didn't win.

Even going back to previous AT&T National events at Congressional, Garrigus has quite a record — this was his 18th round, and he has been over par only three times.

"Everything about this course fits my eye," he said. "If I'm playing well and swinging it good, I feel like I can hit every fairway, just the way everything sets up. They give you perfect targets. There's stuff to aim at. That's what I love."