Arrieta, 27, is 20-25 with a 5.46 ERA (217 ER/358.0 IP) in 69 major league appearances, all but six as a starting pitcher, in all or part of the last four seasons with Baltimore (2010-13). He was originally selected by the Orioles in the fifth round of the 2007 Draft and made his major league debut in 2010 at the age of 24. He was a 10-game winner for the Orioles in 2011, going 10-8 with a 5.05 ERA (67 ER/119.1 IP) in 22 starts. Arrieta has split the last two seasons (2012-13) between Baltimore and Triple-A Norfolk.
The 6-foot-4, 225-pound Arrieta was a member of Baltimore's 2013 Opening Day roster and has had three stints with the big league club this season, going 1-2 with a 7.23 ERA (19 ER/23.2 IP) in five starts. With Norfolk, Arrieta went 5-3 with a 4.41 ERA (24 ER/49.0 IP) in nine appearances (eight starts) this year.
Arrieta was drafted by the Orioles out of Texas Christian University and made his professional debut in 2008. A year later, he advanced as high as Triple-A, combining to go 11-11 with a 3.40 ERA (57 ER/150.2 IP) in 28 starts between Double-A Bowie and Norfolk. He began the 2010 campaign by going 6-2 with a 1.85 ERA (15 ER/73.0 IP) in 12 appearances (11 starts) with Norfolk to earn his first promotion to the big leagues.
Strop, 28, last season served as one of Baltimore's primary set-up men, going 5-2 with three saves, 24 holds and a 2.44 ERA (18 ER/66.1 IP) in 70 relief appearances, all single-season career bests. He tied for seventh in the American League in holds and limited opponents to a .283 slugging percentage, the sixth-lowest mark in the majors among pitchers who made at least 70 appearances.
The 6-foot, 175-pound Strop is 7-6 with three saves and a 4.14 ERA (59 ER/128.1 IP) in 144 major league relief appearances with Texas (2009-11) and Baltimore (2011-13). He missed time on the disabled list this year due to a lower back strain and has gone 0-3 with a 7.25 ERA (18 ER/22.1 IP) in 29 relief outings with Baltimore.
A native of the Dominican Republic, Strop made his major league debut with the Rangers in 2009 and split three seasons between the majors and minors before being traded to Baltimore near the end of the 2011 campaign. He combined to go 2-1 with a 2.05 ERA (5 ER/22.0 IP) in 23 relief appearances that season between Texas and Baltimore before his breakout campaign in 2012.
Feldman, 30, signed a one-year contract with the Cubs prior to the 2013 campaign and went 7-6 with a 3.46 ERA (35 ER/91.0 IP) in 15 starts this season. Overall, Feldman is 46-50 with a 4.66 ERA (424 ER/818.2 IP) in 219 major league games (116 starts) with Texas (2005-12) and the Cubs (2013).
Clevenger, 27, batted .125 (1-for-8) in eight games with the Cubs this season before straining his left oblique on April 13. He batted .327 (17-for-52) in 15 games with Iowa this year.