PEORIA, Ariz. – Jarred Kelenic figures to hit a lot of home runs for the Mariners if things play out to his expectations, but the club’s No. 1 prospect won’t forget the first one.

The 20-year-old outfielder -- the No. 11 overall prospect in baseball, per MLB Pipeline -- smoked a first-pitch fastball from Rockies reliever Alexander Guillen onto the berm beyond the right-field fence at Peoria Stadium in the eighth inning of Seattle’s 9-6 loss to Colorado in Monday’s Cactus League play.

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The 20-year-old brings both confidence and some pop and displayed both on his home run.

“I called it, in the most non-arrogant way possible,” Kelenic said. “I just looked at his fastball and said to Carson [Vitale], our field coordinator, if I get one heater, I’m going to hit it out. I swear. And the rest is history. I don’t know what else to say.”

Kelenic’s prediction was confirmed by manager Scott Servais, who has marveled all spring about how well the youngster thinks ahead and studies the game.

“He said he was going to hit a home run if the guy threw him a fastball, which he did,” Servais said. “So he was pretty excited about it. …. He certainly got all of that one.”

Kelenic, a 2018 first-round Draft pick who was acquired from the Mets in the Robinson Canó/Edwin Díaz trade last year, entered Monday’s game in the sixth inning and went 2-for-2. He is now hitting .357 (5-for-14) with a double and homer in his first Major League camp.

The Mariners expect to have him open the season back at Double-A Arkansas, where he finished last season. But they’re not closing the door on a potential promotion to the Majors sometime this season if he proves ready.

So far this spring the 6-foot, 196-pounder has certainly not been overwhelmed, and he kept things in perspective after Monday’s home run as he hustled out to talk to his parents, grandparents, girlfriend and other family members who had flown out from Wisconsin to see him play this past week.

“I’m just trying to have fun out here," he said. "No matter if I do terrible or do really good. You just saw it. I was out with my family. That’s what means more to me than hitting a home run. It’s fun, but my family means more to me than that.”