A day after first encountering Bryan Abreu, Jurickson Profar remained amazed at the Astros’ broad-shouldered, braces-wearing rookie, who had struck him out on six pitches in a 15-0 win.

Oakland’s second baseman sought an old Texas Rangers teammate to confirm some suspicions. Robinson Chirinos completed batting practice last Tuesday and happily obliged.

“Man,” Profar told the Astros catcher, “that last pitch you threw me. Man, that was nasty.”

Replied Chirinos: “The guys in the video room went crazy (over) how much spin it had.”

Acclaim from Abreu’s second major league outing spread to his third and fourth. On Wednesday, he struck out two of the three A’s he faced at Minute Maid Park. Handed the middle of Kansas City’s order in the ninth inning of a five-run game Saturday, Abreu yielded two singles and struck out Ryan McBroom.

Manager A.J. Hinch removed the rookie from the game with one out to get. Hinch clapped his hands and patted Abreu on the backside before taking the baseball.

“The best thing I like about that kid is his personality,” said Chirinos, who caught Abreu again on Saturday. “He acts like he belongs here in the big leagues. It’s cool to watch for a young pitcher.”

One year after rookie Josh James’ superb September forced his inclusion on both Astros postseason rosters, Abreu might be taking a similar trajectory. The 22-year-old Dominican righthander has six strikeouts in 3⅔ innings since he was summoned as a September call-up.

Abreu began the season with Class A-Advanced Fayetteville and since has authored a rapid rise up the organizational pecking order. Baseball America ranks him behind only Forrest Whitley among Astros pitching prospects.

“He’s nasty,” Hinch said Sunday. “His breaking ball is as good as anyone we have or anyone that we have had over the last few years. You see the funny swings and the uncomfortable takes, and you realize why the organization was so high on him.”

So intrigued was Hinch that, on Saturday, he allowed Abreu to face Jorge Soler, Hunter Dozier and three-time All-Star Alex Gordon over Will Harris, who warmed in the bullpen as insurance if the outing went awry.

“As you see me using him a little bit more, (I’m) certainly challenging the thought of how he could respond to more important innings,” Hinch said Sunday. “Where that leads moving forward? We’ll have to play the games out.”

Conversations about the Astros’ postseason bullpen will not begin until the team clinches a third American League West title, Hinch said. Houston tailors its bullpen so meticulously to combat the strengths of its opponent that little can be truly concrete until a first-round foe is known.

No matter the opponent, three spots have been secured by Will Harris, setup man Ryan Pressly and closer Roberto Osuna.

James, Hector Rondon and Joe Smith are all logical inclusions if they continue to pitch well. If Brad Peacock returns from shoulder and neck issues with effectiveness, he’d ostensibly be the favorite to steal the seventh and final spot in the ALDS bullpen.

But James’ inclusion in last season’s ALDS bullpen presents a counterargument of sorts. The rookie of only 23 major league innings made it instead of Rondon and Smith, two men most considered locks throughout the season for any postseason roster.

James made the roster due to his overpowering swing-and-miss potential and ability to go multiple innings. Albeit during a small sample size, Abreu has shown those traits.

His curveball is considered one of the best in the spin-rate-obsessed organization. Development with his slider, a pitch he can throw harder than his curveball, has been evident, too.

“It’s coming out as a fastball down the middle. Then it just bails,” catcher Martin Maldonado said of the slider. “I’d say he’s a little bit like Pressly. Same repertoire of Pressly.”

The comparison seems apt. Pressly and Abreu complement their devastating secondary stuff with a four-seam fastball that averages around 96 mph.

Pressly’s average spin rate on his breaking pitches is 3,055 revolutions per minute, according to BaseballSavant. That tops the Astros’ pitching staff.

Just behind him? Abreu. On 45 breaking pitches tracked by BaseballSavant, Abreu has averaged 2,883 rpm of spin rate. Twelve have induced swings and misses.

“The spin he has in the slider and the curveball — you don’t see that every day for me as a catcher,” Chirinos said.

Though he’s gone more than one inning only once in four major league outings, Abreu was a starter throughout this minor league season. There is no innings limit for Abreu, who has eclipsed his career high by more than 40 frames.

More concern surrounds whether Abreu can perfect a bullpen routine after receiving five or six days between outings in the minors. Hinch said this past weekend he is not yet ready to test Abreu with outings on back-to-back days.

Other hurdles still stand before Abreu. His fastball command can be imprecise. Hitters will soon have more and more video to dissect. An adjustment will come, and whether Abreu can adjust is still a mystery.

“I feel when he’s going to be able to throw the fastball where he wants to, that’s going to be a game changer for him,” Chirinos said. “That’s the only thing that he’s not getting consistently to the plate.”

After the Astros dealt away most of their upper-level pitching depth at the trade deadline, Abreu’s development was always crucial for 2020. Eleven games remain to see if he can continue his emergence a year early.

“He’s acting like he’s been there before. He follows me and Chirinos. He’s got the stuff to be here, no matter if he’s 22, 19, 25,” Maldonado said. “He’s got the ability to put hitters away and have the hitters look bad.”

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