SEATTLE – Cubs hitting coach Dustin Kelly said Sunday morning that there have been times he has heard audible gasps in the dugout when Michael Busch connects with a baseball. Out of the gates this season, the rookie has been a steady source of loud, hard contact.

Not long after Kelly’s words, Busch dropped jaws again at T-Mobile Park, launching a towering two-run homer off Luis Castillo to help power the North Siders to a 3-2 win over the Mariners. It marked the fourth game in a row that the rookie first baseman belted a home run for the Cubs, putting him one shy of the franchise record.

“The thing that I've been impressed with is the damage that he's capable of doing,” Cubs manager Craig Counsell said earlier this weekend. “That's raw power. That's power that's in there.”

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Busch’s latest homer arrived in the fourth inning, when Castillo sent a 2-2 changeup darting to the bottom of the zone. The rookie hammered the pitch to the tune of a 108.4 mph exit velocity, driving it a projected 437 feet, per Statcast. It was a no-doubter that carried high over right-center field and dropped deep into the stands.

This marks the first time a Cubs player has homered in at least four consecutive games since Christopher Morel did so in five straight in May 2023. That feat by Morel tied a Cubs record, which is shared by Sammy Sosa (June 1998), Ryne Sandberg (August 1989) and Hack Wilson (July 1928).

“It's always nice to get off to a good start,” Busch said earlier this weekend. “My favorite part about it is, when you play well, you're only helping the team. But obviously, we're still in April. So, let's just keep building and keep working and try to keep going.”

True, it remains very early in the season, but a strong start can do wonders for a player like Busch, who is navigating his first full season in the big leagues.

The Cubs acquired Busch in January via trade and from the jump made it clear he would step in as the everyday first baseman. Counsell went as far as saying Busch had “conquered” the Minor Leagues when discussing the youngster during Cubs Convention over the winter. This type of start can fuel not only Chicago’s belief in Busch, but his own confidence.

“It is affirmation,” Counsell said. “And that's important.”

With his 2-for-4 showing on Sunday, Busch now has a .327/.393/.694 slash line through 15 games with a team-leading five homers to go with 11 RBIs. Following a 2-for-13 start in his first five games with the Cubs, Busch has hit at a .389 (14-for-36) clip in his past 10 contests.

Entering Sunday’s game in Seattle, Statcast had the 26-year-old Busch ranked in the 99th percentile in expected slugging percentage (.731), the 98th percentile in expected weighted on-base average (.467), the 95th percentile in Barrel rate (17.6%), the 90th percentile in expected average (.320) and the 88th percentile in average exit velocity (92.7 mph).

Even further underneath the statistical hood, Busch headed into the afternoon with a .357 average and .679 slugging percentage off fastballs (all types). That was only through 30 plate appearances ending with heaters, but it was nonetheless a promising improvement over his limited showing with the Dodgers in ‘23 (.118 BA and .147 SLG in 40 PA).

“Part of what some of the knock was with him last year was that he struggled with the four-seam fastball elevated away -- like every hitter does,” Kelly said. “It's really just part of the natural adjustment that these guys make, and the good ones make them a lot quicker. And I think we're seeing that with Michael.”

After Dansby Swanson led off the fourth with a double, Busch said he was just trying to get a pitch from Castillo up or inside that he could attack “in an aggressive way” to move the runner over. The decisive pitch from the Mariners’ righty did not get under the zone enough to elude the rookie’s bat.

“I think he left the changeup a little too far up,” Busch said, “and kind of right in my sweet spot.”

Counsell has repeatedly described Busch – from his personality to his plate appearances – as consistent. The power streak has taken that to the extreme.

“You hit homers in four straight games – you just don't say that very often about anybody,” Counsell said. “He's really, really kind of driving the bus for us offensively the last couple days.”