SAN DIEGO -- Center fielder Jackson Merrill didn’t get what he wanted for his 21st birthday. There was only one thing on the rookie’s wish list: a Padres victory.

“That’s all I want,” he said. “That’s all I’m asking for.”

Alas, the series opener Friday night at Petco Park went the Blue Jays’ way, 5-1. But MLB’s third-youngest player continued to display why the Padres promoted him before he could order his first legal adult beverage.

Merrill became the first Padres player in the franchise’s 56 seasons to record a hit on his 21st birthday.

Merrill turned an unusual hit into a hustle double in the second inning, as his 107.3 mph smash grounder went through the webbing of first baseman Vladimir Guerrero’s glove. He maintained his typical game awareness and aggressiveness on offense despite being tested in center field as he rarely has this season.

In the top of the first inning, Blue Jays designated hitter Justin Turner sent a long drive to center field. Merrill, with barely a month of center-field experience, sized it up, got to the wall and was situated for his first home run robbery. He leaped … and missed the ball by a few inches. Merrill sat dejectedly on the warning track as Turner took his trot.

“It just kept carrying,” Merrill said. “You can’t really simulate that. You just go home, come back the next day and if it happens again, be more prepared. It’s a tough play.”

An inning later, with two runners aboard, Merrill was tested by a tricky 103.4 liner off the bat of Kevin Kiermaier. Once the ball started bouncing on the outfield grass, it spun away from Merrill’s charge in the left-center gap. Merrill, a converted shortstop who, of course, throws right-handed, tried to backhand the ball with his glove hand. He did stop the ball, but it dropped to the grass.

Merrill had to take a step back to pick up the ball, and the Blue Jays continued in full sprint on the bases. Kiermaier wound up with a double, and both runners scored to highlight a four-run inning by Toronto.

Those two defensive plays go onto the short list of things that haven’t gone Merrill’s way this season. The list of things that have gone his way is considerably longer.

Merrill carries a slash line of .329/.397/.443 after his first 22 big league games, and you’ll see him among the rookie leaders in just about any category. He’s drawn raves in the clubhouse, and his ability to learn center field on the fly has plugged the biggest hole the team had coming into Spring Training.

“It shocks me how young he still is,” said starting pitcher Matt Waldron, who threw 33 pitches in that decisive second inning. “I love his work ethic, his attitude, how competitive he is. I think it rubs off on all of us.”

Added manager Mike Shildt: “First class, a real pro. He’s mature beyond his years, not only in how he plays, but how he conducts himself, his heart for competition, his heart for winning. I think he genuinely meant that the biggest thing he wanted for his birthday was for us to win the game.”

Merrill clearly loves the challenge in front of him. And he loves the game itself. When the Padres had an off-day on Thursday, he drove 75 miles north to watch the Padres’ Single-A affiliate, the Lake Elsinore Storm.

“It was just cool to go see the people I trained with in the offseason, to go see them play,” Merrill said, singling out former Minor League teammate Wyatt Hoffman. “... It never hurts to go watch more baseball. No matter the level, you might learn something.”