KANSAS CITY -- In an organization that carries a rich tradition of third basemen, Matt Chapman joined a select group in Monday night’s 19-4 win over the Royals at Kauffman Stadium.

With the game well in hand due to an early onslaught by the A’s offense, the Royals decided to preserve their bullpen by sending outfielder Alex Gordon to the mound in the seventh. After taking a pair of fastballs out of the zone, Chapman got one on the outer part of the plate and unloaded for a majestic solo home run that came off the bat at 105.4 mph and sailed into the left-field seats at a projected 447 feet, per Statcast.

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In a victory that tied the A’s with Tampa Bay for the second American League Wild Card, the solo blast was Chapman’s 30th homer of the season, marking the first time he’s reached that milestone in his career. He is just the third A’s third baseman to reach the 30-homer mark, joining Sal Bando (1969) and Eric Chavez, who did it back-to-back seasons (2001-02).

“That’s pretty fast company to be in,” manager Bob Melvin said. “On top of that, what he brings defensively, his leadership qualities, this guy is going to be a star. You want to say this is a breakout year, but it’s not. He had a terrific year last year, too. He’s going to get better and better. Probably not going to be his last 30-home run year.”

Chapman had no idea what type of company he had joined until it was mentioned to him after the game. After hearing the short list, he was surprised there weren’t more third basemen to hit 30 for Oakland, especially the ones he grew up watching.

“I figured Josh Donaldson would have probably done it,” Chapman said. “That’s cool. That’s good company.”

Chapman’s historic feat was just a piece of the most impressive performance turned in by the A’s offense this season. On a night where all nine batters in the starting lineup recorded at least one hit and run scored, Oakland’s 19 runs and 22 hits were season highs. Both were the club’s highest totals since scoring 21 runs on 22 hits on Sept. 20, 2018, against the Angels.

Marcus Semien led the offensive eruption with a career-high seven RBIs, joining Miguel Tejada as just the second shortstop in A’s history to drive in seven runs in one game. Semien supplied the big hit in back-to-back five run innings, belting a three-run triple that chased Royals starter Brad Keller in the second before smacking a three-run homer into the left-field fountains off Jorge Lopez.

“I’m just trying to get the job done with a runner on third and less than two outs,” Semien said of his first two at-bats. “Just took the swing I needed to take to get in the air on the first one, and on the second one, I just got ahead in the count and got something close. Those felt great.”

The homer was Semien’s 23rd. He sits at 69 RBIs, which is remarkable given his usual placement in the leadoff spot. Also showing off vastly improved defense with a 12.2 defensive rating, fourth-best among MLB shortstops, Semien is putting together arguably the best all-around season of his career.

“The numbers are just starting to get off the charts for a leadoff hitter,” Melvin said. “The defense that he brings. The production, the power, it’s fun to watch.”

The rout of Kansas City falls in line with what the A’s have been doing against AL Central clubs for the better part of three years now. Oakland is now 18-5 against the division this season, outscoring its opponents, 149-71. Since Aug. 23, 2016, the A’s are 70-24 against the Central.

A first for Puk

After two pressure-packed appearances to begin his Major League career, left-hander A.J. Puk had a chance to breathe a little bit in outing No. 3.

Puk, who is ranked the club’s No. 2 prospect by MLB Pipeline, showed the skills that earned him such high praise in the Minors with two scoreless innings.

The southpaw entered the game in the top of the seventh in relief of starter Homer Bailey and Puk immediately struck out Nicky Lopez on a slider, recording his first big league strikeout. It was the first of two on the night, as Puk allowed just one walk and no hits.

“I think it was important to let him get in there and settle, throw some pitches, and go back out again. Just get comfortable,” Melvin said. “You can see what we’re excited about. His slider was sharper today, and once he got into the swing of things, his fastball was locating better.”

After feeling the adrenaline rush a bit more at the Oakland Coliseum in his first two outings that came in close games, Puk was able to relax this time around with a 13-run lead.

“I think both outings, my heart rate was getting up there,” Puk said. “Those close ballgames are a great experience. I took both of those as something to learn from to build for my next outing.”