ARLINGTON — The Astros added four players to their 40-man roster before Wednesday’s 7 p.m. deadline to protect them from selection in the Rule 5 Draft.

Righthanded pitchers Cristian Javier, Enoli Paredes and Nivaldo Rodriguez, along with first baseman Taylor Jones, will bring Houston’s 40-man roster to 38 players.

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Any Rule 5 eligible player not on a team’s 40-man roster is eligible for selection during the draft in December. Players selected in the Rule 5 Draft must remain on that team’s 25-man roster for the entire season or be returned to their original club.

The addition of Jones, Paredes and Javier — all within MLBPipeline’s Top 30 Astros prospects — was expected. Though tabbed No. 26 in those same rankings, Rodriguez was a relative unknown.

A 22-year-old Venezuelan righthander who was signed for $10,000 in 2016, Rodriguez has never pitched above Class A Advanced. The Astros protected Bryan Abreu from Rule 5 selection last season despite never pitching above Class A, so there was obvious precedent.

Rodriguez had a 2.50 ERA and struck out 9.8 batters per nine in 105 innings this season. He throws three pitches primarily — fastball, curveball and changeup — and, unsurprisingly, his curveball spin is renowned within the organization.

Javier was the organization’s minor league pitcher of the year, ascending from Class A Advanced Fayetteville to Class AAA Round Rock during a breakout season. The organization considered calling Javier up in September. General manager Jeff Luhnow called him a candidate to enter Houston’s major league rotation at some point in 2020, but intimated Javier is likely to start 2020 in Class AAA.

The 22-year-old Javier harnesses the best command of any young, Latin arm in Houston’s system. His four-seam fastball resides in the low 90s. A slider is his most frequent out pitch, but Javier continued to improve his changeup this season. Javier allowed hitters just a .130 batting average — lowest among all minor league pitchers who threw at least 100 innings — and struck out 13.5 per nine.

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Paredes is a tad behind Javier in his trajectory. Paredes has thrown just 50 innings above Class A Advanced. He struck out 128 in 94 innings between A Advanced and Class AA Corpus Christi last season, producing a miniscule 0.979 WHIP.

Including Seth Beer in the trade for Zack Greinke last July left the Astros without much organizational depth at first base. Starter Yuli Gurriel is entering his last season under club control. Both Kyle Tucker and Yordan Alvarez have experimented there, but neither is ready to take significant major league time.

Enter Jones, who authored a fine season with Class AAA Round Rock. Houston considered calling him up last season, but opted for Abraham Toro due to Toro’s defensive versatility. The 6-7 Jones was selected in the 19th round of the 2016 Draft. He had an .889 OPS, 50 extra-base hits and 112 strikeouts in 531 plate appearances with the Express.

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