Having made the cut for the sixth time in six major appearances following opening rounds of 71-73 on the California coast, the young Scot was level-par for the day standing less than 100 yards from the hole at the par-5 18th.
But, instead of the birdie he had in his sights, MacIntyre closed with a bogey for a 72 and a one-over total, sitting just outside the top 30 heading into today’s final circuit.
“It was solid to start off with,” said MacIntyre of a front nine that contained one birdie and one bogey along with seven pars.
“Back nine I struggled. I think I hit three greens on the back nine, two of them on the last two. Terrible wedge shot on 18, just disappointed with the finish, but that's golf.”
MacIntyre reckoned it had been a missed opportunity overall, adding: “The score is there for the taking. I just didn't take my chances.
“It's a golf course that will punish you if you're off line. Thankfully I've had my short game with me. If I've been out of position, I've been trying to hit it in the bunker.
“I've been doing that, and my bunker play is as good as most. So I just trust myself. If you can get it in the bunker, you can control what you're doing. If you hit it in the rough, you've got no chance.
“If you're out of position, try and hit it in the bunkers. Other than that, get it in play off the tee, which I had been doing all week until today really. I just struggled, didn't feel comfortable, but that's golf.”
The left-hander has enjoyed his first taste of Torrey Pines, saying: “It's been brilliant. I didn't know what to expect. Obviously, I watched the normal PGA Tour event here, and you see guys spinning it back.
“I knew coming for the US Open, it was going to be nothing like that. It's exactly how I imagined it.
“Reminds me a bit of watching Pebble Beach, the style of golf, the way the greens are, stuff like that. So it's been a great experience.”