The Astros have one of the better international scouting departments in baseball, and they have used that to consistently strengthen their big league club. Yet, they've done so more by using hard-throwing international signees in trades rather than actually promoting those players to Houston.

In a swap of big league relievers (Roberto Osuna and Ken Giles), the Astros also sent promising pitchers Hector Perez and David Paulino to the rebuilding Blue Jays. Paulino was a trade acquisition of the Astros back when he was in the lowest levels of the Tigers' farm system, but Perez is yet another Astros international signing who has been traded away to acquire big league help.

Before Perez, the Astros also dealt righthander Jorge Alcala (signed out of the Dominican Republic) in the Ryan Pressly trade. They also traded Franklin Perez (signed out of Venezuela) as the headliner in last year’s Justin Verlander trade. Righthanders Jorge Guzman and Albert Abreu were traded to the Yankees for Brian McCann.

One of the themes of these trades is the Astros sign “older” pitching prospects and help them develop their velocity. Perez, Guzman and Alcala all originally signed as 18-year-olds, while Abreu signed one month short of his 18th birthday and didn’t make his pro debut until he was 18. All four have ended up having upper-90s to 100 mph fastballs, which helped them develop into highly tradable prospects.

This particular move is controversial because the Astros are acquiring a player in Roberto Osuna who is wrapping up a 75-game suspension for violating baseball’s domestic violence policy earlier this year.

BLUE JAYS ACQUIRE:

Ken Giles, RHP

Age: 27

If anyone needed a change of scenery, it’s Giles. An extremely effective closer for the Phillies and Astros for much of the past three seasons, Giles' sporadic struggles of the past turned into a full-blown slump this season. Giles still throws nearly as hard as he ever did (97-99 mph), but his fastball has proven much more hittable this year, even as he throws plenty of strikes. The Astros eventually demoted him to Triple-A Fresno to see if it would help, but Giles has proven just as hittable in Triple-A as he was in the majors.

Giles has a history of being extremely hard on himself, and his stuff and control is still major league-caliber, so a move to a less-pressured environment in Toronto may be helpful for him to get back on track. Giles is arbitration-eligible after the season but won’t reach free agency until 2021.

Hector Perez, RHP

Age: 22

After signing as an 18-year-old, Perez has quickly made up for lost time. He recently had been promoted to Double-A Corpus Christi after minor improvements in his delivery helped him show improved control in his final month with high Class A Buies Creek. Perez always has a mid- to upper-90s fastball that can blow some hitters away, but it’s less effective when he has bouts of wildness. His control wavers from below-average to average. Perez throws an extremely hard, 88-90 mph slider with modest depth and he’s improved his splitter that serves as his changeup. At the least, he should be an effective power reliever for the Blue Jays. But if he can continue to improve his secondary pitches and his control, he has the makings of a potential mid-rotation starter.

David Paulino, RHP

Age: 24

Paulino has long been one of the most talented pitchers in the Astros' farm system, but he also has been one of the most frustrating. Between injuries and a suspension, the 6-foot-7 Paulino has thrown just 273.1 innings in eight pro seasons and he’s never thrown more than 90 innings in a season. Paulino has missed time with Tommy John surgery, a disciplinary suspension, elbow soreness, bone chips in his elbow and an 80-game suspension for testing positive for a performance-enhancing drug.

This year, he’s missed most of the season with a shoulder injury, although he has returned to action and was working on a rehab assignment in the Rookie-level Gulf Coast League. If Paulino tests positive again, he will be suspended for a full season. Paulino’s fastball isn’t as firm as it was at his best in 2015-2016, but it’s still a potential plus pitch with plenty of angle and velocity. His curveball gives him a second plus offering. His changeup has even flashed plus as well, although getting all three synced up has been difficult because Paulino has missed so much time. Paulino is a perfect buy-low candidate to acquire in a trade. His struggles to stay healthy may prevent him from reaching his still-lofty ceiling, but if he puts it all together he could still be a mid-rotation starter or an elite reliever.

ASTROS ACQUIRE:

Roberto Osuna, RHP

Age: 23

A player who is suspended for performance-enhancing drugs during the season is ineligible to play in the postseason. Major League Baseball does not have any such rule for players suspended for domestic violence, so Osuna, who is eligible to return from a 75-game suspension on Aug. 4, will be eligible to pitch in the playoffs for the Astros. Osuna’s domestic assault case is still underway in Canada.

Strictly on the field, the Astros are getting one of the best relievers on the trade market. Osuna threw just 15 innings before his leave of absence and suspension began. He mixes a mid-90s fastball and a plus slider, plus a cutter and changeup. Once he returns, Osuna will bolster what was already a deep Astros bullpen, filling the void that Giles created.