The Scot found himself in the same group as DeChambeau when the Californian made his European Tour debut in the 2016 Abu Dhabi HSBC Championship.
They were in one of the last groups out in the opening round, which saw DeChambeau card an eight-under-par 64 to hold the lead at Abu Dhabi Golf Club.
After subsequent rounds of 72-78-72, he eventually finished joint-54th in an event won by another American, Rickie Fowler.
“Even then, he had a completely different way of playing the game with the same-length clubs and his upright posture,” recalled Drysdale as he prepared for this week’s Commercial Bank Masters in Doha.“The first day, he shot eight under and looked like a potential world No 1 – it was awesome to watch, and he wasn’t short then off the tee. He’s hitting it miles now.
“The next day he hit it all over the place. He looked completely different over the two days.”
In just over five years, DeChambeau has become a major champion thanks to a brilliant victory in last year’s US Open at Winged Foot and claimed his eighth PGA Tour title in the Arnold Palmer Invitational at Bay Hill on Sunday.
That success lifted the 27-year-old to sixth in the world rankings heading into this week’s Players’ Championship at TPC Sawgrass in Florida
“I saw him in the Middle East last year then the start of this year in Saudi, he’s literally twice the size he was four or five years ago,” added Drysdale of DeChambeau having bulked up in his quest to push himself to new boundaries.
“I walked the back nine in Saudi and he was playing the pro-am. No 12 is a 450-yard par-4 and there’s a bunker on the right about 300 yards to get into and 325 to get past. He was 30 yards by that bunker with a 3-wood. It’s a completely different game.
“I’ve played with Rory [McIlroy], but he just seems to have moved the needle on the distance debate.
“I saw a lot on social media of him hitting the tee shot on six at the Arnold Palmer and taking lines that are 370 carry over water - that’s doing me in the air by 90 yards."
Drysdale, who lost to Jorge Campillo in a five-hole play-off 12 months ago, is among 10 Scots in this week’s European Tour field in Doha.
The 45-year-old is still hoping to land an elusive first European Tour victory before calling it a day and says Lee Westwood who turns 48 soon, going toe-to-toe in Florida on Sunday had been inspirational.
“What a player Lee has been for the last 25 years,” said the Borderer. “He’s made ten Ryder Cup appearances and I’m sure he’ll make an 11th this year.
“Incredible consistency to be in the top 50 for as long as he’s been. He’s not all that far off 48. It’s nice to see if you keep fit and injury free, which I haven’t the last couple of years.
“But I’ve been working hard on that and there might be a few more years in me yet.”