At altitude. Get ready to hear that term ad nauseam at this week’s WGC–Mexico Championship, so much so it might make for a fun drinking game while you’re watching the telecast. Both golf and imbibing are, after all, affected considerably by altitude.

But what does that actually mean?

Distance has been a hot topic in golf lately, and this week it will get even more attention when tour pros play Club de Golf Chapultepec, home of the WGC event since 2017, which sits 7,600 feet (2,300 metres) above sea level. Thin air equals less resistance equals ball go (very) far. Though just how far is a bit more complex than that.

Players need to account for that added distance by re-calculating the actual distance to what it would be at a normal altitude. They do so by multiplying the distance by a fixed point (10 percent, as one example) then subtract that from the actual distance to figure out the effective distance, which is what will determine what club to hit.

“There’s also uphill shots – the ball is in the air less so I’ll take into account a lower percentage to adjust for – and there’s downhill, where I might play a higher percentage,” Webb Simpson said. “But shot trajectory matters, too. If I’m hitting it lower, we’ll [adjust] 10 percent. If I’m hitting it higher, we’ll play 16 percent. There’s a lot more to it than a number.”

Examples abound.

On the 526-metre par-5 15th, for instance, Simpson’s second shot during a practice round measured seven metres uphill. But his ball was on a downslope, which meant his hybrid was going to come off the face lower than usual, so he only adjusted his distance by about 9 percent.

On the 411-metre par-4 10th, though, his 9-iron approach was playing nine metres downhill. Playing from a flat lie and with the ball in the air longer, he said he might adjust by 15 percent or more.

“This week, it’s like we have half clubs in our bag, so it’s like we have 23 clubs,” Simpson said. “In the States, [a] high [ball flight] doesn’t always translate to farther, though.

“If you’re dialled in this week and communicating what shot you’re going to hit, you have a lot of good options.”

Still, the adjustment has admittedly been a struggle for Simpson, whose best finish in two previous appearances was a T-37.

Paul Tesori, Webb Simpson
Simpson and his caddie, Paul Tesori, have some extra work to do figuring out distances this week. [Photo: Harry How/Getty Images]

Collin Morikawa, meanwhile, is playing his first WGC–Mexico Championship, but the tour rookie has experience playing at altitude (drink!), specifically at the Barracuda Championship outside Reno in Nevada, where he won his maiden PGA Tour title last July. That experience should help him this week.

“This is a really fun course to play because there are different clubs you can hit,” Morikawa, 23, said. “Leaving yourself 200 yards out isn’t that bad – it’s a little cut 7-iron. You just have to make sure you don’t skip any steps this week because you could be over the green or way short.”

Morikawa’s focus then is simply trying to hit the distances he plays at sea level, and adjust from there. For example, his gap wedge normally flies 120 metres. This week, it’s a club he would likely use from closer to 145 metres, depending on the variables.

“It’s a lot of trust this week,” he said. “You’re going to hit good shots that turn out bad. But everyone is different. Some guys will focus more on TrackMan data.”

None more so than Bryson DeChambeau, who earlier in the week employed two TrackMan devices on the driving range to dial in his numbers that he’ll use for his calculations this week.

Naturally, DeChambeau’s scientific mindset takes a certain amount of enjoyment from such an experience. Swinging at 187mph and flying a drive 363 metres brings a smile, too.

But getting adjusted to playing at altitude (drink!), at least according to DeChambeau, is a lot simpler than it’s made out to be.

“We use the normalised numbers we get on two devices on the range that tells us how far it goes, and we use the one that’s the most consistent over time as our baseline,” he said. “That’s it. People think I go through these crazy processes, but I’m just trying to simplify the process.”

The same goes for most every player competing.