MINNEAPOLIS — It was a simple two-out walk. Seemed innocent enough at the time, but it turned out to be one of the game’s biggest plays.

Carlos Santana’s walk in the second inning was the springboard to a six-run two-out rally, which was all the Twins needed to beat the Royals 8-3 on Monday night at Target Field.

The Royals scored in the first two innings off starter Pablo López (11-8) to take a 2-0 lead. Meanwhile, Royals starter Brady Singer (8-8) appeared to be locked in from the start, retiring five of the first six Twins hitters, four of them via strikeout.

But he issued a two-out walk to Santana, which triggered a long-overdue outburst for the Twins, who were held to four total runs over their two previous games, both losses to Cleveland.

Ryan Jeffers and Austin Martin singled, with the latter driving home Santana for the Twins’ first run. Then All-Star utility man Willi Castro drove a pitch into the flower beds above the fence in right-center field for his ninth homer of the season, giving Minnesota a 4-2 lead.

“I was just focused, especially with two men on base, and I got a good swing on it,” said Castro, who tied his career high with his ninth homer of the season.

But the Twins weren’t done yet. Trevor Larnach singled before Royce Lewis blasted a full-count sinker off the facing of the second deck in left for his 15th home run in just 40 games played this season.

The six-run rally was only possible because Santana — who has the most career plate appearances of anyone on the Twins’ roster — didn’t give away an at-bat in a spot where it’s easy for a batter to lose his concentration.

“There are situations in games where it’s kind of normal sometimes for players to get a little bigger with their swings, try to do a little more,” manager Rocco Baldelli said. “Guys … go up [to the plate] just kind of swinging for the fences. Two outs, you can see that. Nobody on, two outs.

“But there’s a professionalism in just staying very, very consistent with what you’re going to swing at and what you’re trying to do at the plate. Those little things lead to big things, and they lead to big innings and wins.”

López had an interesting perspective on the rally, as he had to rush from the clubhouse back to the dugout after Singer retired the first two batters on just five pitches.

“I had just changed my undershirt, my jersey, there were two outs, I was tucking it in, and then stuff just started happening,” López said. “That’s the kind of offense that we have. We can make stuff happen with two outs. We can make stuff happen when the other team doesn’t make a play or they give us a free pass.

“It started with a two-out walk from Carlos Santana — good at-bat and then that momentum kept building up and building up, they kept the line moving and it was fun to watch from the dugout.”

Lewis capped it with a home run after an eight-pitch at-bat that included four straight foul balls, one of which broke his bat. It was the last of his supply of that particular model, so he turned to a black bat that he claims he doesn’t like as much.

“I got that new bat and I was like, ‘Hopefully we can make this one work,’” Lewis said. “And then my next at-bat, [Royals catcher Salvador Perez] was joking with me, like, ‘I think you made it work.’ I said, ‘I still don’t like it.’”

The win gave the Twins a 6-2 record this year against the Royals, who now lead Kansas City by 1 1/2 games for the second Wild Card spot in the American League. With the Guardians beating the Cubs in Cleveland, the Twins remained 3 1/2 games out of first place — not that they’re paying attention to the standings at this point.

“You’re aware of it, but we like to be in the mindset that we control our own destiny,” López said. “Like, we know right now we’re trailing the Cleveland Guardians, who are playing good ball. But from now on, every series is the most important one. We come into the clubhouse with a good mentality, expecting to win and making stuff happen within the things we can control.”