Ever since he turned professional following the 2016 US Open, Jon Rahm has had one man on his bag.
That man is Adam Hayes.
Hayes is one of the most experienced caddies on the PGA Tour, having looped on the world's most lucrative golf circuit since 2004.
Prior to that, he spent four years caddying on the LPGA from 1999 to 2003 where he estimates he made $400 a week.
In those four years, he worked for seven different players and regularly split hotel rooms with three different caddies just to be able to afford the bill.
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His first PGA Tour bag came when he teamed up with Vaughn Taylor in 2004. They teamed-up to good effect and got their first win that season in the Reno-Tahoe Open.
He subsequently went on to caddie for the likes of Webb Simpson, Jason Dufner, Ben Crane and, more recently, Russell Henley.
He was also memorably on the bag for Jonathan Byrd, when the American had a hole-in-one in a playoff to win the 2010 Justin Timberlake Shriners Hospitals for Children Open in Las Vegas.
Hayes left Henley in mid-2016 to take up the bag of Rahm after flying to Phoenix to meet with the Spaniard and his now-wife Kelley.
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“Before I went to work for him I wanted to make sure we got along and that our personalities didn’t clash or anything, so we spent a couple nice days together and played some golf and hung out," Hayes told The Caddie Network website.
“He’s become not only a boss but he’s a good friend, I attended his wedding and we just have a really cool relationship where when we are off the course, we are off the course and when we are on the course, we keep it very business-like. I think it’s really worked out well.”