PEORIA, Ariz. -- Jackson Merrill's first big league camp is off to quite a start.

The Padres’ top prospect in the MLB Pipeline rankings will make an out at some point. (Probably.) But in the team’s Cactus League opener against Seattle on Friday afternoon, Merrill went 3-for-3 while showing off his knack for using all fields and getting his barrel to the baseball. He showcased a solid glove at shortstop, as well, and he flew around the bases to score from first on Matthew Batten's double, the Padres' first run in a 3-2 loss to the Mariners.

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"I think Jackson Merrill's a pretty good player," Padres manager Bob Melvin said with a wry smile. "... He does not look like a teenager, that's for sure."

Merrill's spring is about to get awfully busy, too. With three-fourths of the Padres' starting infield slated to play in the World Baseball Classic next month, the 19-year-old is expected to receive quite a few Cactus League starts.

"I'm excited for that," said Merrill, a first-round Draft choice in 2021. "I don't want the guys to leave. But when they do, and I'm in there a lot of the time, it's going to be really fun for me."

Already, Melvin has committed to starting Merrill at shortstop on Saturday, when the Padres face the White Sox at Camelback Ranch. The skipper has come away impressed with what he’s seen early in camp.

“You talk to him, you watch him go about his business, you watch his work ethic -- it’s everything you want,” Melvin said. “This guy’s going to be a pretty quick mover, I think, in this organization. You come up there, you get three hits. You get righties, lefties, good at-bats every time. He’s a calm thinker. It’s impressive.”

The lefty-hitting Merrill posted a slash line of .339/.395/.511 last season between Rookie ball and Single-A Lake Elsinore. With the Padres’ infield set, he’s not a serious candidate for a big league roster spot. But as Melvin noted, many in the organization feel he’ll force their hand soon enough.

Not that Merrill concerns himself with that chatter.

“I just try to play in the present,” he said. “I don't really think ahead; I just think of where I am right now.”

A few other observations from the Padres' Cactus League opener (played, with the pitch timer, in a crisp two hours, 29 minutes):

• Right-hander Nick Martinez struck out four over two scoreless innings as he begins to build toward a starting role for Team USA at the World Baseball Classic.

"We were attacking the zone with all pitches," Martinez said. "It felt good."

Martinez's first outing at the WBC is slated for March 12 against Team Mexico, Melvin revealed. That should give Martinez two more spring outings with the Padres before he joins Team USA.

• Spring Training: the perfect time for a bit of trial and error, right?

Friday marked the first game in which left-hander Ryan Weathers had used a PitchCom device on his belt. The device is designed to allow Weathers to press a button that calls a pitch for his catcher. In that sense, it did its job -- though Weathers might need to rethink where he places the device on his belt.

Weathers threw 35 pitches, and he estimated that on about 30 of them, his glove arm nicked the device. That meant ...

"As I was letting go of the ball, I could hear in my head the opposite pitch of what I was throwing," Weathers said.

Even pitches that aren't in his arsenal: "One of them, I threw a fastball up, and it said, 'Screwball.' I'm not [Brent] Honeywell, so I don't throw a screwball."

Despite the snafu, Weathers was mostly sharp, striking out three over two innings, though he allowed a trio of unearned runs.

• Those unearned runs scored after Juan Soto dropped a relatively routine fly ball in shallow left field. Sure, it's only one spring blunder in an exhibition game. But it's also a worthwhile reminder that Soto will be making the transition from right to left field this spring, and it might take him some time to acclimate.