HOUSTON — It’s expected now that Jonathan Broxton will put the Royals through a roller-coaster ride each time he gets the call to secure a close victory. He is a jumbo-size human stress test whose efforts are not for the weak-hearted.

It happened again Wednesday afternoon when he wiggled free from a first-and-third jam with one out in the ninth inning to preserve a 2-1 victory over the Houston Astros at Minute Maid Park.

That’s 6 feet 4 and 300 pounds of wiggle.

“Q asked him Tuesday night,” center fielder Jarrod Dyson said while nodding toward catcher Humberto Quintero, “ ‘Hey, Brox, can we just get a one-two-three for a change?’ No. Brox keeps us on our toes.”

Broxton worked around a leadoff walk Tuesday night in preserving a 2-0 victory for Luke Hochevar. That was child’s play compared to Wednesday’s high-wire act that secured a victory for Bruce Chen.

Chris Snyder opened the Houston ninth with a single to left, which brought pitcher David Carpenter into the game as a pinch-runner.

Mike Moustakas then made a terrific stop at third on Matt Downs’ hard grounder up the line. From his knees, Moustakas threw for the force. Downs avoided a double play by beating Yuniesky Betancourt’s throw to first, but the Royals had a key out.

“All year, guys have been making huge plays,” Broxton said. “Not just for me, but for our starters and the other bullpen guys. Our defense has been solid. That’s what is going to win you games — defense and pitching.”

It was the latest defensive gem from Moustakas, who preserved a Broxton save last Friday in St. Louis by throwing a strike to the plate for the final out of the game after chasing down an errant throw in foul territory.

This time, Moustakas was guarding the line.

“I’m playing no-doubles,” he said. “(Downs) hit a little topper down the line because Brox made a great pitch. I just tried to get in front of it. I caught it and got it over to Yuni and let Yuni do the rest.”

More drama followed when José Altuve grounded a hit-and-run single through the left side that moved Downs to third with one out. Broxton responded by striking out Brian Bixler.

“You’ve got to empty out the tank right there,” Broxton said. “There’s no sense in saving it.”

Broxton then ended the game by retiring Jordan Schafer on a fly to left.

How’s your heart?

“It never runs,” said Alex Gordon, who caught the final out. “I know he always gets in those tough situations because we always only give him a one-run lead. He finds a way to get it done.”

Almost always. Broxton has 18 saves in 21 chances this season while sporting a 1.57 ERA in 28 appearances. Let’s face it: Those are All-Star-quality numbers from a guy whose resume sports two previous All-Star selections while pitching for the Dodgers.

But the Royals — and their fans — grew accustomed in recent years to Joakim Soria’s cool efficiency. Switching to Broxton’s cardiac closing act is no small adjustment.

“Some closers are like that,” manager Ned Yost said. “I don’t want to say it’s fun going through it, but there is a little degree of fun because you have a lot of confidence knowing that, no matter what happens, nine times out of 10, he’s going to get out of it.”

The victory enabled the Royals to win the three-game series, after dropping Monday’s opener, and complete a 4-2 road trip. They also climbed back to within five games of .500 at 31-36.

That’s notable because five-under matches their high-water mark since a 12-game April losing streak dropped them to 3-14. They also closed, temporarily, to within four games of first-place Cleveland in the American League Central Division

“Our goal all along after the streak was to get back to .500 by the All-Star Game,” Yost said. “That’s a pretty lofty goal after being 11 games under .500, but we keep plugging at it and keep winning series.”

Chen, 6-6, held the Astros to one run in 52/3 innings before Kelvin Herrera, José Mijares and Greg Holland got the game to Broxton.

“That rough stretch that we had in April,” Chen said, “most people would take it as a negative. But we’re using it as a positive. It’s helping us to become the team that we are.

“It’s been a long road. We always feel like we’re trying to catch up to .500, but this is a very good team.”

Chen and the bullpen had to be good because the Royals managed just two runs and three hits against Houston starter Jordan Lyles, 1-4, in seven innings.

“We did not have good swings at him,” Yost said. “When you’ve got to take chances and score both of your runs on contact plays. …We gambled both times. Luckily, we scored both runs, and it was the difference in the game.”

Moustakas opened the fourth with a double and came around on infield grounders by Alcides Escobar and Brayan Peña. Gordon ripped a one-out triple in the fifth and scored when shortstop Jed Lowrie misplayed Betancourt’s grounder for an error.

“We were going on contact both times,” Gordon said, “and were able to put some pressure on them. We were able to score two runs and, the way our pitching has been lately, that’s all that we need.”

Chen carried the 2-0 lead into Houston sixth but began the inning by walking Schafer and Carlos Lee. Those were Chen’s first walks of the game.

“I fell behind (and walked) the first guy,” Chen said. “It’s a close ballgame, I don’t want to leave anything over the plate for the guy (Lee) who is the best hitter in their lineup.”

An escape route opened when J.D. Martinez’s broken-bat grounder to short turned into a double play, but Chen fell behind 3-0 on Lowrie before surrendering an infield single.

Escobar gloved the ball with dive up the middle but had no play as Schafer scored. It was the Astros’ first run in 15 innings dating to the five-run eighth Monday against Louis Coleman in a 9-7 victory.

Chris Johnson followed with a single between short and third, which moved Lowrie to second and finished Chen.

Kelvin Herrera’s first pitch got away from Peña for a passed ball that moved the runners to second and third. But Herrera stranded both runners by striking out Snyder. Herrera then struck out the side in the seventh.

Mijares replaced Herrera to start the eighth but departed after striking out Schafer. In came Holland, who pulled a Broxton by working into and out of a jam. Then came another Broxton thrill ride.

“I love it,” Moustakas said. “Every time he comes in, we feel like the game’s over. Every time.”

Just make sure to hold on tight.