In 2012, the year after Bryce Harper and Mike Trout showcased their skills in Arizona, it was Yelich's turn to see how he matched up with the top prospects in the game.
The best of the best traditionally wind up in Arizona in October and November, and Yelich didn't disappoint when he spent his autumn in the desert. Then 20, he was coming off a sensational season at Class A Jupiter, batting .330 with a .404 on-base percentage, along with 12 home runs, 29 doubles, five triples and 48 RBIs. He scored 76 runs in 106 games.
A teammate of Jose Fernandez that season, Jupiter finished as the runner-up in the Florida State League. The left-handed hitter with the sweet swing was a natural choice to spend the fall of 2012 in Arizona.
"You kind of get to meet the top guys from other systems," said Yelich, now 22. "Guys you hopefully are playing against the next few years. It was cool. I liked it. It was unique."
The atmosphere was calming, scenic and all business. Basically nobody, besides scouts, was in the stands.
"Literally, the only people in the stands are the scouts," Yelich said. "That's kind of cool because you have to perform.
"That's the first time you kind of play against higher competition. It's a lot of Double-A and Triple-A guys. Maybe some guys with some big league time sprinkled in. That was my first time playing above A-ball. I played low-A, high-A, and in the fall I went over there."
Yelich did his part to stand out, batting .301 (28-for-93) with six doubles, a triple and 11 RBIs in 25 games.
From a personal side, the atmosphere was different, because he was playing baseball at a time football was in full swing.
"It is a little more laid back," Yelich said. "It's different than anything else. It's hard to explain because it is really high-level competition, and nobody is in the stands. You are playing in October and November. You're playing almost to Thanksgiving. It was cool to play against guys from other systems."
To play in October is every prospect's dream, because the goal is to reach the playoffs. What stood out was continuing towards the holiday season, and playing baseball while local families were making their Thanksgiving preparations.
"It wasn't weird playing in October," said Yelich, who played for the Phoenix Desert Dogs. "Everybody eventually wants to play in October. But when you're like, 'Hey, Thanksgiving is in a week!' That was kind of weird to be still playing."
The AFL class of 2012 had its share of noteworthy prospects, including Cody Asche (Phillies), Kolten Wong (Cardinals) and Didi Gregorius (D-backs).
Yelich also got to play against a center fielder in the Blue Jays' system named Jake Marisnick, another athletic young talent who batted .314 in 19 fall games.
Yelich competed against Marisnick in the Florida State League. The two knew each other in passing, and were standouts growing up in California. But during the Arizona Fall League, news broke that Marisnick was part of a major trade between Miami and Toronto.
Marisnick was one of seven players headed to Miami. The deal was finalized days later, but in the meantime, Yelich reached out to his soon-to-be new teammate.
"I heard about Jake and knew of him coming up through high school and showcases," Yelich said. "He got traded when in the Fall League. I said to him, 'Here is my number, welcome aboard. If you need anything, here is my number.'
"He texted me the first few days before Spring Training. We kind of hung together, and have been good friends ever since."