HOUSTON -- Nelson Velázquez hit two home runs in the first three innings as part of the Royals’ four-homer barrage as Kansas City won its sixth straight game, 6-5, over the Astros on Sunday afternoon at Minute Maid Park.

Velázquez hit solo home runs in the second and third innings, Matt Duffy had a two-run homer in the second, and Salvador Perez crushed a two-run homer in the third as the Royals built a 6-2 lead.

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“The lead was the difference in the game,” Kansas City manager Matt Quatraro said. “We didn’t do anything after that. Nellie, we’ve seen he’s a game changer to all fields -- put two opposite-field home runs. That’s really impressive. Salvy coming back and getting his, and of course, we all knew Duff would hit a home run today. One in April and one in September.”

Astros rookie Hunter Brown yielded all four Royals homers.

“We were ready,” Velázquez said. “We know he throws hard. We know he has a good breaking ball. We stayed on the fastball all day. That was our approach against him. We stayed on it and made some good swings.”

Perez’s homer went a projected 410 feet and had an exit velocity of 109.4 mph, per Statcast. Perez was activated off the seven-day concussion injured list prior to the game Sunday.

“Every time you hit a home run, you feel happy, especially if we win,” Perez said.

Kansas City swept a series in Houston for the first time since April 15-17, 2014. The Royals have won four straight series, their longest such streak since they won four consecutive series Aug. 30-Sept. 12, 2019.

During the Royals’ six-game winning streak, Kansas City has scored at least six runs in five games. The Royals have won 10 of their last 11 games.

During the win streak, five victories come by two runs or fewer.

“I think there’s an opportunity for growth there,” Quatraro said of winning close games. “We’ve had a lot of close games this year that haven’t gone our way. And early on, we were using that as kind of a, 'They’re learning. They’re learning to be in close games.’ And maybe this is the byproduct of that.”

Alec Marsh pitched well as the bulk pitcher out of the bullpen, yielding four runs (three earned) on three hits with six strikeouts in 5 1/3 innings.

Marsh said he was able to make adjustments after the first two innings of his outing. He called it an “amazing team win.”

“I woke up this morning and knew it was a big game,” Marsh said. “I had a lot of adrenaline and stuff going on just because I know we’re not playing for a bunch, but our goal to come in here was to make them sweat for their last part of the season. We treated it as a playoff-type atmosphere, which it was.”

Following Marsh out of the bullpen, Tucker Davidson, Carlos Hernández and James McArthur combined to throw 2 2/3 scoreless innings. It was McArthur’s third save of the season.

“McArthur getting the heart of order and especially getting [Yordan] Alvarez, as he did the other night -- that’s really hard to do,” Quatraro said. “Carlos, I feel really happy for him. We know he’s had a tough stretch. But to come here two days in a row and pitch big, important innings for us. You can’t overlook Davidson coming in there to get the two lefties out [Alvarez and Kyle Tucker], which is no easy task.”

The six-game winning streak is the longest active streak in the Majors and the Royals’ second-longest streak of the season behind a seven-game winning streak from July 28-Aug. 4.

“It’s just giving us confidence for the future knowing that we can go into someone else’s park and we stack up right with them,” Marsh said. “As young as we are, the guys are learning, the guys are gaining experience. To be able to come in here into their park and get a sweep is amazing.”