The pair were on opposite sides in the 2017 Walker Cup in Los Angeles, where MacIntyre beat Cameron Champ in the first-day singles before finishing all square in a rematch 24 hours later.
But, speaking as he prepared to make his debut in the abrdn Scottish Open at The Renaissance Club, Zalatoris revealed he crossed paths with MacIntyre before then.
“I've known Bob since 2015 from the brief time he was at McNeese State and I was at Wake Forest,” said the world No 30 of MacIntyre’s spell at college in Louisiana. “He drives it I think the best I've ever seen out of anybody.
"I played with him at Bel-Air the first two days of the US Am (in 2017). Bel-Air is 6,700 yards, very short, very tight and he's just out there ripping drivers down the middle of fairways between trees and water.
“I'm hitting 3-irons and thinking I'm doing all right, and he's flipping wedges in and shoots 65 and I'm shooting 68.
“Bob is a great guy. He keeps me in stitches every time I'm around him, he's so funny. He's one of my good buds out here on the European Tour.”
Zalatoris, who finished second behind Hideki Matsuyama in this year’s Masters, was on a family trip the only other time he played golf in Scotland.
“My family made the mistake of going to London four days before, and all I wanted to do was play golf,” he recalled.