HOUSTON -- The Astros added four players to their 40-man roster on Wednesday, several hours ahead of the 7 p.m. CT deadline to protect players from exposure to the Rule 5 Draft.

Right-handed pitchers Cristian Javier, Enoli Paredes and Nivaldo Rodriguez as well as infielder Taylor Jones join the roster, which now stands at 38. Among those left unprotected who rank in the Astros’ Top 30 prospect list per MLB Pipeline are shortstop/third baseman Jonathan Arauz and outfielder Ronnie Dawson. They will be eligible to be selected by another team during the Rule 5 Draft on Dec. 12 at the Winter Meetings in San Diego.

Javier, the organization's ninth-ranked prospect per MLB Pipeline, was named the Astros' Minor League Pitcher of the Year in a 2019 season that was split between three levels in Houston's Minor League system. In 26 outings (18 starts) with Triple-A Round Rock (two games), Double-A Corpus Christi (17 games) and Class A Advanced Fayetteville (seven games), Javier posted an 8-3 record with four saves, a 1.74 ERA and 170 strikeouts.

Among all Minor League pitchers with at least 100 innings pitched, the 22-year-old Javier ranked first in opponent batting average (.130), second in ERA, third in strikeout rate (37.3 percent), sixth in strikeouts and eighth in WHIP (0.97).

Paredes went 5-4 with a 2.78 ERA across 22 appearances, including 12 starts, between Corpus Christi (12 games) and Fayetteville (10 games). The 24-year-old compiled 128 strikeouts, while allowing 50 hits, a .155 opponent batting average and a 0.98 WHIP in 94 innings. He's the Astros' No. 13 prospect.

Rodriguez, the organization's No. 26 prospect, finished 6-6 with a 2.40 ERA and a 0.99 WHIP over 24 games, including 15 starts, between Fayetteville (18 games) and Class A Quad Cities (six games) in 2019. The 22-year-old struck out over a hitter per inning and allowed a .183 opponent batting average.

The 25-year-old Jones spent his entire 2019 season at Round Rock, hitting .291 with 28 doubles, 22 home runs, 84 RBIs and an .889 OPS. Primarily a first baseman entering the 2019 season, the 6-foot-7 Jones started at four different positions this season. Houston's No. 28 prospect made 64 starts at first base, 27 in left field, 14 at third base and two in right field.

Dawson may be the more enticing prospect of the two players left unprotected. The 24-year-old, ranked as Houston's 16th-best prospect per MLB Pipeline, impressed the Astros during Spring Training in 2019 after revamping his swing and slimming down in an effort to increase his speed and agility. He played 103 games at Double-A and 10 at Triple-A last season, combining for a .207/.313/.385 slash line while recording 50 walks and 14 stolen bases.

The Astros' second-round Draft pick in 2016, Dawson was behind several outfielders in an organization with significant depth in that area, and he may be intriguing to a club lacking such a logjam at the top.

Arauz, 21, batted .249/.319/.388 over 115 games for Fayetteville (87 games) and Corpus Christi (28 games) in 2019. He is Houston's No. 25 prospect. 

Players first signed at age 18 must be added to 40-man rosters within five seasons or they become eligible to be drafted by other organizations through the Rule 5 process. Players signed at 19 years or older have to be protected within four seasons. Clubs pay $100,000 to select a player in the Major League phase of the Rule 5 Draft. If that player doesn't stay on the 25-man roster for the full season, he must be offered back to his former team for $50,000.

For this year, that means an international or high school Draft pick signed in 2015 -- assuming he was 18 or younger as of June 8 of that year -- has to be protected. A college player taken in the '16 Draft is in the same position.