The box score from the Cubs’ 7-1 win over the Washington Nationals on Thursday will highlight Ian Happ’s three-hit, four-RBI game.

It won’t tell the full story of his crucial, potentially game-changing defensive play that happened in the third inning.

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With one out, Robert Hassell III laced a hit to left field and rounded first while looking to take the extra base. Happ corralled the ball and rifled a strike to second. Nico Hoerner caught his throw and tagged Hassell for the second out of the frame.

“Nico and I have done that a lot,” Happ told Marquee Sports Network’s Taylor McGregor after the win. “We haven’t had a lot of opportunities this year, yet. Just getting it in the vicinity.

“Nico with a great tag. He does that so well — go grab that ball and get to the bag really quickly. It was awesome.”

OK, so there were two outs. Why was it such a crucial moment?

Because of what happened after. CJ Abrams followed with a double, which probably scores Hassell and makes it a 3-1 game with Happ’s throw and Hoerner’s tag. Ahmed Rosario followed with an infield single that caromed off Matt Shaw’s glove at third base that moved Abrams to third.

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Colin Rea induced a flyout from James Wood to end the inning. But if you’re following this hypothetical scenario and there’s one out instead of two, it’s potentially a sacrifice fly and a 3-2 game.

Instead, Happ’s defensive prowess meant the Nationals were kept scoreless.

Rea settled in and pitched 5.1 innings of relief after that – the Cubs used Drew Pomeranz as an opener. The Cubs bats would tack on two more runs in the sixth and ninth innings to close out the win, racking up 15 hits in the contest.

Happ’s play was the second outfield assist of the game. Kyle Tucker nabbed Abrams in the first inning as the shortstop tried to stretch a single to lead off the game. The offense has been the story of the season for the Cubs – but the defense, which was expected to be their staple, has been steady, too.

“I think you saw it today, all around,” Happ said. “The play Tuck made, Pete [Crow-Armstrong] running down balls in center. A couple other tough plays by Tuck, the infield defense. Just really suffocating. I think when our pitchers are in the zone, dominating like that, that gives us a leg up.”