Jon Rahm watches his shot from the 16th tee during the first round of the Arnold Palmer Invitational. Richard Heathcote

The difference between Arnold Palmer Invitational leader Jon Rahm and second place after one round is two shots. But the difference between the World No. 1 and his fellow PGA Tour pros is probably the standards he holds himself to.

Most PGA Tour pros would look at Rahm’s seven-under-par 65 at Bay Hill—last season the fourth-hardest golf course on tour—and think the Spaniard played perfect golf.

Not Rahm. Not the man who has won three PGA Tour events in this calendar year and has victories in five of his last nine starts worldwide.

Asked if he was firing on all cylinders Thursday, Rahm answered with “no.”

So, what could improve? “Gosh, go through the round and you’ll see plenty of mistakes,” Rahm said. “I just took advantage of, let’s say, minimizing mistakes and I converted a couple situations into really good scores. But it can always be better.”

Last year’s PGA Tour Rookie of the Year, Cameron Young, shot a five-under-par 67 at Bay Hill to sit just two behind Rahm, along with Chris Kirk, who won the Honda Classic last week, and Kurt Kitayama. Eight players are at four under, including the star trio of Jordan Spieth, defending champion Scottie Scheffler and Rickie Fowler.

To be fair to Rahm, he was just answering a question. And, if you’re splitting hairs, you could point out Rahm found eight of 14 fairways, which contributed to missing five greens. But the context needed is that warm, windy Orlando is fast drying out Bay Hill’s narrow fairways and even good drives are finding the gnarly rough.

“Those fairways are getting firm and they’re not easy to hit,” Rahm said. “When you miss the fairway, you’re going to be chopping it out of the rough and hoping for dear life.”

Rahm didn’t need to hope for dear life with his short game, which allowed him to save par four times from those five missed greens. A tricky lie in the greenside bunker at the par-3 14th and a 35-footer for par at the next kept his back nine bogey-free for a 31.

“That one on 15 was huge. I made my worst swing of the day,” he said. “I accepted making a bogey; I put it in a bad position off the tee. [But] sometimes you make ‘em like that.”

He also made ‘em when there were birdie and eagle putts. Or, as the former U.S. Open champion described it, he “converted a couple situations.”

Those situations included a trio of birdies to start his round. A bogey at the par-4 eighth was offset by a birdie at the par-5 12th. The last three holes, Rahm showed why he’s won five times worldwide since August. A towering 5-iron from the fairway at the par-5 16th set up a 24-foot eagle putt he drained for his first-ever eagle at Bay Hill. Rahm then hit his tee shot at the par-3 17th to two feet, and then his approach to six feet on the 18th. He made both to finish four under in his last three holes.

Asked which was better, his opening three holes or closing three, Rahm said, “I can’t believe I’m saying this, but if I’m going to be as picky as possible, I struck it and hit better quality shots on the first three, but that’s just nit-picking. I heeled my 3-wood on 18. I slightly over-faded my 5-iron on 16. And then that’s about it. That’s all I can say. But if I go by difficulty of holes, I think obviously the last three holes you take it.”

Most would certainly take it on around one of the most difficult trio of closing holes on the PGA Tour. Even Tiger Woods, who won eight times at Bay Hill, would likely take four under in that stretch.

So, does anything need to improve for Rahm to hold on over the next three rounds and capture a fourth PGA Tour win before April?

“It’s the first day,” Rahm said with a smile. “Ask me that on Sunday if I keep playing like this and I’ll probably change my answer.”