CASTLE ROCK, Colo. – After unleashing another mammoth drive that sailed even farther than usual, Rory McIlroy picked up his launch monitor and started running through his amped-up yardages here at Castle Pines.

At sea level, he said, his 54-degree sand wedge falls out of the sky at 128 yards. But here, at 6,400 feet, it’s 145.

A stock, 195-yard 7-iron at home now goes 222 yards.

And his greatest weapon, the driver? He’s the second-longest player on Tour, statistically, averaging 319 yards per drive. But that number, he said, gets ramped up anywhere between 350 and 375 yards.

He shared those tidbits, of course, with an amused grin.

It’s the penultimate week of the FedExCup season, and players and caddies have more on their mind than points standings and money lists. Castle Pines, host of the BMW Championship for the first time in a decade, presents a unique challenge where competitors are also factoring in altered carry distances, trajectory, temperature, wind direction and even the time of day.

So, is it a fun one-off? Or is it, with players positioning for $25 million, a competitive nuisance?

“I’ve been on Tour for 18 years at this point,” McIlroy said Wednesday, “so anything new and different is nice. Like, seriously. It’s a different challenge than what we face week-in and week-out, and I think that’s great.”

As an international player, McIlroy has more experience than most dialing in his revamped yardages; he boasts a stout playing record in the thinner air of Mexico, South Africa and Switzerland. There are little tricks he’s picked up along the way. Such as: The ball doesn’t curve as much at altitude, so he reins in his starting lines. And: “If you’re between clubs, I think that you can always get the shorter club there if you want to. If you hit it harder – for me, anyway – it goes higher and just gets there.”

Moments later, in the eighth fairway, McIlroy failed to heed his own advice. He tried to take a bit off a 5-iron from about 250 yards. But he mis-hit it slightly, and his shot didn’t carry the false front on the par 5. So he reached back into the bag for a 6-iron – and the high, soaring mid-iron landed in the middle of the green and settled just past the flag.

Similar recalibrations were happening all over the course Wednesday.

A significant factor in Scottie Scheffler’s iron-play preeminence is his distance control, and that aspect is put to the test this week. Without wanting to divulge too much, Scheffler said that his caddie, Ted Scott, never alters the settings on his Trackman, no matter where they are in the world, and that Scott relies on his own system to ensure that Scheffler is hitting his shots as close to pin-high as possible.

This week, Scheffler said, “we have our numbers and how far the ball goes here, and we still have our numbers at home. So we have two ways we’re trying to do it, depending on the shot, just to where I know that I can get comfortable with the shot we’re trying to hit.”

So Scott can either give Scheffler the at-home number, or calculate the “new” number based on altitude-related factors such as time of day and uphill/downhill shots that affect hang time.

“There’s a lot of work that goes into it,” Scheffler said, “so it’s a pretty big adjustment for us.”
It’s merely tapping into an old habit for Wyndham Clark, who grew up playing Castle Pines as a kid and sported a dominant junior and amateur record in the state. But even Clark thought his hometown advantage might be overblown this week.

“Altitude is tough to play at, and I’m not here that much playing golf,” said Clark, who now calls Scottsdale, Arizona, home. “So I’m a little rusty on my altitude game. But the good thing is I am used to it, and I feel like I have some tricks up my sleeve when I get into certain situations. Maybe it’ll come with shot selection and distance control.”

What’s the chief challenge?

“There’s a little inconsistency in the thin air and altitude depending on how high you hit it,” he said. That means a 185-yard 7-iron at sea level can, in these conditions, go anywhere from 200 to 215 yards. “If anyone seems to err, to go long or short, it’s probably because of trajectory. That’s going to be the challenge. Everyone is going to have a good idea of how far they’re hitting the clubs, but you can sometimes just hit one forever in Colorado.”

And it’s a completely foreign concept to Viktor Hovland, who grew up in Norway, played college golf at Oklahoma State and didn’t land on Tour while there was still a World Golf Championship event in Mexico City that was played at just less than 8,000 feet.

“I’m just trying to learn as much as possible,” said Hovland, and in three days he’s learned, most of all, to be more accepting with his approach play. Ordinarily, he said, if he missed his target with a pitching wedge by 6 or 7 yards, he’s grumbling to himself about a poor effort.

But not now. Not here.

“I think you’ve got to be a little bit kind to yourself when your distance control is maybe a little off,” Hovland said, “because there’s a lot of variance. You don’t know how much it’s going to be affected.”

Of course, there’s more to it than just additional number-crunching for the caddies. Xander Schauffele said, half-jokingly, that he might bash driver more often so he can catch his breath by the time he gets to his ball, and that players who arrive on the tee first could be “huffing and puffing a little bit more than normal.” After getting winded in a workout, Scheffler was thankful he went on vacation last month to Telluride, which sits at 8,750 feet in southwest Colorado, to get somewhat acclimated.

Still, he said, “That elevation got to me a little bit.”

It did, too, when Scheffler apprenticed for a year on the Korn Ferry Tour, playing in both Colorado and Colombia. Both weeks, he recalled having fitful sleep, like feeling as though he couldn’t breathe or being jarred awake by strange dreams.

“Just weird stuff,” he said.

And that makes for compelling competition — at least for one week.