Clubs pay $50,000 to select a player in the Rule 5 Draft, to be held on Dec. 6 at the conclusion of the Winter Meetings in Nashville. 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 $25,000.
With the additions, the Reds' 40-man roster currently sits at 39 players.
Corcino skipped a level by going from low Class A Dayton to Double-A Pensacola. In 26 starts, the 22-year-old was 8-8 with a 3.01 ERA, 65 walks, 111 hits and 126 strikeouts in 143 1/3 innings. In June, the Dominican pitcher took part in a tandem no-hitter by throwing the first eight innings before reaching his pitch limit.
Rodriguez, 20, struggled to bat .156 in 23 games at Class A-Advanced Bakersfield before he was sent back to Dayton. With the Dragons, he batted .271 with six homers and 44 RBIs in 65 games. Rodriguez was signed as a teenager out of Venezuela in 2008.
A 21-year-old reliever from the Dominican Republic, Contreras posted a 3.12 ERA in 49 games with Dayton and Bakersfield. He spent most of the season in the Midwest League, where he had 19 walks with 51 strikeouts in 50 2/3 innings.
Partch, who just completed a stint in the Arizona Fall League, was a 26th-round pick in the 2007 First-Year Player Draft. In 52 regular-season games, including seven near the end at Pensacola after playing with Bakersfield, he was 7-4 with a 4.26 ERA. The 26-year-old had 36 walks and 79 strikeouts over 82 1/3 innings.
A fifth-round pick in the 2006 Draft, Ravin was limited to 23 games this season because of an oblique injury. Twenty of those relief appearances were at Pensacola, where he was 1-3 with a 5.25 ERA. It was the 24-year-old Ravin's first year as a reliever after being a starter his whole career.
In 15 games, including 14 starts for Rookie-level Billings and Dayton, Guillon was 6-1 with a 2.38 ERA, 61 hits, 31 walks and 90 strikeouts over 75 2/3 innings. The 20-year-old was signed as a free agent out of Venezuela in 2008.
Mark Sheldon is a reporter for MLB.com. Read his blog, Mark My Word, and follow him on Twitter @m_sheldon. This story was not subject to the approval of Major League Baseball or its clubs.