Jon Rahm
(Golfweek Photo)

Last week, he earned the low-amateur honor at the U.S. Open as the only non-professional to make the cut and finished T-23. He then turned pro, to much fanfare, earlier this week, and on Wednesday was named Golweek‘s College Player of the Year for his 2015-16 senior season at Arizona State.

But then he one-upped himself on Thursday.

In his first round as a professional, Rahm, 21, of Barrika, Spain, fired a 7-under 64 in the opening round of the Quicken Loans National, taking a one-shot lead.

Rahm never made a mistake all day at Congressional Country Club’s Blue Course in Bethesda, Md., with seven birdies and 11 pars.

Clearly, the former World No. 1 amateur and two-time Ben Hogan Award winner was not feeling anxious about his debut among the big boys.

“I would say about five months ago, my expectations were really high, but coming into this moment, I worked with my mental coach to keep — we basically just narrow it down to enjoying it and learning as much as I could,” Rahm told The Washington Post. “I’ve been thinking like that for the last month and trying not to have high expectations.”

Thus, a 2-hour-15-minute weather delay to the start of play Thursday wasn’t going to faze Rahm. Once play resumed, Jhonattan Vegas’ 6-under 65 was the closest anyone could do to matching Rahm’s score. Eight players posted 5-under 66s.

Rickie Fowler, the top-ranked player in the field, bounced back a bit from three straight missed cuts and shot a 3-under 68. Following his T-2 at Oakmont, Jim Furyk struggled to a 2-over 73.

“I was just hot off the tee,” Rahm said. “I was really comfortable off the tee. I was hitting fairways and I was hitting it long, so it allowed me to be more aggressive.”

Rahm, who tied for fifth at the Waste Management Phoenix Open earlier this year after he had tied for 10th in the fall at the OHL Classic at Mayakoba, has started his recent run with former Sun Devils teammate Ben Shur on the bag.

Shur toted for Rahm at last week’s U.S. Open.

It was Shur’s astute eye that actually put Rahm on the track toward moving to a longer putter that allowed him to surge in his senior spring season. Apparently, he’s in Rahm’s head – in a good way.

“(Ben) knows exactly what I’m thinking at every point,” Rahm told The Washington Post. “A lot of times, he’s already grabbed the golf club I’m going to hit before I even say. Having someone who knows me so well, it’s certainly an advantage. He knows what I can and can’t do, and he knows when to stop me on my feet when it’s needed.”

In fact according to The Post, Shur is so in tune that he wrote down that Rahm would not make a bogey all day after his opening tee shot at No. 10 found the par-3 green. He was right.

Four holes later, Rahm already was 2 under. A 30-footer at No. 5 to reach 5 under put him on the final run to have the leading round (and, as Shur predicted: no bogeys).

After 18 holes, things look pretty good for Rahm. But he got some advice from Jack Nicklaus at the trophy ceremony after the U.S. Open.

And Rahm is sticking to the Golden Bear’s humbling principles.

“He told me to just be myself and to not try to do more than what I can do,” Rahm said. “I certainly put that on today, and I just played some of the best golf I can play.”