HOUSTON -- The Royals are rolling right now, and they’re not looking to stop any time soon. 

With a tone-setting start by Daniel Lynch and an offense that backed him up with 13 hits, the Royals won their fourth straight game and seventh of their last eight with a 7-1 victory over the Astros on Monday night at Minute Maid Park. 

Less than a week after taking three of four against the Astros in Kansas City, the Royals didn’t let up Monday night in Houston. The win clinched a season series victory over the Astros for the first time since 2017 (4-3) after going 1-5 in both 2018 and ‘19. 

“I think it’s more just building off yesterday,” manager Mike Matheny said of the momentum the Royals are gaining. “And each day, just taking something positive that we’ve been doing.”

Here are three key components that propelled them toward their fourth consecutive road win: 

Salvy’s new career high 

Salvador Perez is racing toward 40 home runs this season, and he hit his 33rd of the season on Monday night. Perez took former Royal Zack Greinke deep in the third inning, depositing a fastball in the Crawford Boxes to give the Royals a one-run lead before blowing the game open with a two-run seventh inning and three-run eighth inning.

The RBI was also Perez’s 81st of the season -- a new career high for the Royals catcher who keeps smashing milestones in 2021. 

“Salvy being Salvy,” Matheny said. 

Perez’s two hits Monday were part of the Royals’ 13 total after racking up 16 on Sunday. Whit Merrifield -- who was a homer shy of the cycle -- and Emmanuel Rivera each had three-hit nights, and Perez was on base five times with two walks and reaching on an error.

Lynch’s navigation in the fifth

Against the same team that he held to one run on four hits over seven innings last week, Lynch navigated trouble without much damage in five-plus innings on Monday. The Astros just saw the Royals rookie six days ago in Kansas City, yet they were baffled by his slider and thrown off by his sinker, a pitch he threw more than usual to go with a different approach against one of the best offenses in the Majors.

Lynch’s biggest spot came in the fifth inning. He loaded the bases with a walk issued to Martín Maldonado, a double by Jose Altuve and a walk to Yuli Gurriel. Lynch had gotten behind in the count to Gurriel, so he danced around the zone, opting instead to face left-handed-hitting Yordan Alvarez.

“I thought I made two pretty good pitches to Gurriel, but they got called balls ... but I was actually OK to walk him there with two outs to get to the lefty,” Lynch said. “So that’s kind of what we went for. We didn’t want to give him something, since it seemed like he was seeing me pretty well.”

Lynch threw a first-pitch slider for a ball but then went back to the pitch again, and Alvarez swung, hitting a grounder into the shift for the out. 

“He’s right in the middle of their order, too,” Matheny said. “Tough assignment. … He seemed to just make quality pitches. A lot of young pitchers aren’t going to be able to execute behind-in-the-count changeups, sliders for strikes, sliders below the zone. Just a really impressive mix today.” 

Tapia shoves in relief

Lynch went back out for the sixth inning at 78 pitches, but the Astros put two runners on with no outs to end his night. Domingo Tapia took over and swiftly worked around the trouble, striking out Jake Meyers swinging on a 98.9 mph sinker and inducing a double play chopper that Rivera handled smoothly. It kept the Royals’ lead intact and allowed the offense to build on it in the late innings.

“To me, that’s the game right there,” Matheny said. “In a 2-1 game, Tapia coming in, getting the swing and miss and then the ground ball. That’s impressive. He’s been really good, just coming in and pounding the zone. Really heavy sink and just keeps getting better.” 

Tapia has come up big in these situations all month, and he seems to be getting better with each outing. The righty has allowed just one run in 12 appearances (11 innings) in August. 

The trade the Royals made with Seattle in July, acquiring Tapia for cash, is looking more and more like a win. The 30-year-old has a high-velocity sinker and a nasty slider, and he’s learning to command his offspeed better to allow the two pitches to play off each other. 

“You have to be confident,” Tapia said through interpreter Luis Perez. “Always trying to throw strikes. If I throw strikes, I have a 99 percent chance of getting people out.”