Meet Jordan Spieth's caddie, Michael Greller

Surely you've heard of Jordan Spieth, the three-time major champion who's currently ranked No. 9 in the world. But who is his caddie, Michael Greller?

The former math teacher who used to caddie in his free time first carried Spieth's bag at the 2011 U.S. Junior Amateur at Gold Mountain Golf Club, where Spieth won -- and the rest is history.

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Credit Justin Thomas for setting up the pair after Greller caddied for Thomas at the 2010 U.S. Amateur. Thomas then recommended Greller to Spieth the following year.

Arguably the most famous interaction between the golfer and his caddy came at the 2017 Travelers Championship, where Spieth holed out from a bunker for a birdie to win the tournament in suddden death, causing Spieth to toss his club and chest bump Greller in celebration.

When did Michael Greller start caddying for Jordan Spieth?

Greller started carrying Spieth's bags full-time in 2012 after he first caddied for the former No. 1 amateur golfer in the world in 2011.

What was Greller's occupation before he started caddying for Spieth?

Greller was a sixth grade math teacher at Narrow View Intermediate School who lived in Gig Harbor, Washington.

How did Greller meet Spieth?

Greller met Spieth through a six-year chain reaction of interactions between golfers and the caddie at the amateur level. Greller went to the 2006 U.S. Amateur Public Links Championship and offered to caddie for a golfer named Matt Savage, who was carrying his own bag. Savage later introduced Greller to Justin Thomas, then Thomas recommended Greller to Spieth.

Where is Greller from?

Greller is from Michigan. He and Spieth, who's from Dallas, have playful banter about their respective teams in Michigan and Texas.

Watch Spieth and Greller discuss bunker shot strategies on the 8th hole during the 2017 PGA Championship at Quail Hollow.

Sources: The Dallas Morning News, The Seattle Times, The Washington Post