HOUSTON -- Few debuts in A's history have come with as much anticipation as the fanfare surrounding the one for young phenom Jesus Luzardo. After getting the call to the Majors on Monday, the left-hander finally took a big league mound for the first time on Wednesday night, and he lived up to the hype.

Luzardo emerged from the A's bullpen at Minute Maid Park to begin the bottom of the sixth inning in relief of starter Brett Anderson with a three-run lead. Luzardo, the A's No. 1 prospect and the No. 3 left-handed prospect in baseball per MLB Pipeline, was electric, retiring nine of the 10 batters he faced with two strikeouts in a 5-3 victory over the Astros.

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"I was just anxious to get on the mound. A little nervous, but after the first pitch, it all went away and I just zoned in," said Luzardo, who worked three innings. "Especially after the first, once I went out for the second, I felt like I got in a groove. All my pitches were working, so I was happy to get them over the plate."

The 21-year-old Luzardo's blazing fastball was as good as advertised, topping out at 98 mph as he fired it past Aledmys Diaz and Myles Straw for a pair of punchouts in his first big league inning.

His one blemish came in the sixth on a solo home run surrendered to Martin Maldonado, but as he did in Spring Training by impressing A's manager Bob Melvin and the coaching staff with his poise, Luzardo quickly shook off the homer and settled in.

"We've always known he's mature beyond his years," Melvin said. "It's just getting him healthy and trying to find the right spot for him. He's been a starter his whole career and has done some piggyback stuff before, so we felt that was the best thing to do with him."

Luzardo retired the final seven batters he faced, getting the top three batters in the Astros' lineup on just 10 pitches in the seventh before inducing groundouts from Alex Bregman, Yordan Alvarez and Diaz for a seven-pitch eighth.

"I grew up watching some of these guys," Luzardo said of Houston's star hitters. "I took the same approach I would in any other game, looking at scouting reports in the bullpen and preparing myself for what was to come. The results turned out well."

A four-pitch arsenal was on display for Luzardo. He threw two-seam and four-seam fastballs, a changeup and slider, with 22 of 36 pitches for strikes. His ability to generate a high volume of swing-and-misses will likely be shown off before season's end -- he recorded only one on Wednesday.

Luzardo kept the ball low in the zone with supreme command of his fastball to induce five groundouts and two flyouts, in addition to the two strikeouts.

It was a debut that had the attention of each one of his teammates watching, even Anderson, who by the time Luzardo entered in relief was down in the clubhouse cooling off after five innings of two-run ball before earning his first win against Houston since 2013.

"It's really impressive, the command and poise, for how young he is," Anderson said of Luzardo. "The stuff is phenomenal. Any time you can have a lefty throw 98 [mph] that throws strikes, it's always a plus. Not the easiest situation to come in, and other than a fastball to Maldonado, he was phenomenal."

Behind the plate for Luzardo's debut was rookie Sean Murphy, the A's No. 3 prospect who spent the majority of the past two seasons catching throughout the Minors. With Murphy also supplying some offensive support in the form of a sixth-inning solo shot, his fourth homer of the season and third in the past two days, Wednesday was a sneak peek at the exciting future that lies ahead with so many of the A's top prospects now contributing in a playoff race.

It's a young group the A's hope can soon challenge the longtime division-kingpin Astros for the AL West crown.

"If you look across the way, and I know a little bit about their future, they've got some really good young arms," Astros manager AJ Hinch said of Oakland's farm system. "That's the first time I've seen [Luzardo] live and the first time our hitters had seen him, other than some guys had seen him in the Minor Leagues. It looks like he's got a good arm and a bright future."

Luzardo walked off the mound after Diaz's groundout capped off his night with a calm stride as he kept a stoic look on his face. Meanwhile, a group of about 30 friends and family members who made the trip from his home state of Florida went wild in Minute Maid Park's lower level with roars of cheers as they watched young No. 44 fulfill his childhood dream.

"When I came off in the third inning, I looked up and saw them all," Luzardo said. "I tried not to pay attention. I know they were going crazy, though."

Liam Hendriks took over in the ninth, turning in a 1-2-3 frame to record his 20th save of the year.

When asked when Luzardo might appear in another game, Melvin said, “We still want to get his pitch count up since he is a starter by trade. All our starters are pitching pretty well right now, so maybe the next time out in the same type of fashion. We’ll get together tomorrow and put a plan together for him.”