Sweeney, 28, is a career .280 hitter (481-for-1,719) with 102 doubles, 12 triples, 14 home runs and 185 RBI in 535 games covering all or part of seven big league seasons with the White Sox (2006-07), Athletics (2008-11) and Red Sox (2012). He has a .338 on-base percentage and a .378 slugging percentage, good for a .715 OPS. Sweeney has spent time at all three outfield positions with 318 games in right field, 172 games in center field and 78 games in left field. His .994 fielding percentage ranks third-best among all major league outfielders since the start of the 2006 season.
The left-handed batter and thrower went to spring training with the Red Sox this year but was released on March 30. Sweeney signed a minor league deal with the Cubs on April 3 and batted .337 (28-for-83) with two doubles, two triples, six home runs, 16 RBI and a 1.022 OPS in 23 games with Iowa.
The 6-foot-4, 225-pound Sweeney set several career highs with the Athletics in 2009 when he hit .293 (142-for-484) with 31 doubles, three triples, six home runs and 53 RBI in 134 games. A right knee injury limited Sweeney to 82 games in 2010. Upon his return, he batted .265 (70-for-264) with 11 doubles in 108 games in 2011, his final year in Oakland, and hit .260 (53-for-204) with 19 doubles in 63 games with the Red Sox last season.
A native of Cedar Rapids, Sweeney was originally selected by the White Sox in the second round of the 2003 Draft.
Dolis, 25, has posted no record, one save and a 3.52 ERA (3 ER/7.2 IP) in eight relief appearances with Iowa this season. He joins the Cubs for the second time this year, as he was up for a brief stint April 13-15, appearing in one game (April 14 vs. San Francisco) and recording 0.1 scoreless innings. He has seen action with the Cubs each of the last three seasons, going 2-4 with four saves and a 6.13 ERA (27 ER/39.2 IP) in 36 career big league relief appearances.
The righthander made the Cubs Opening Day roster last season and had three stints with the club, going 2-4 with four saves and a 6.39 ERA (27 ER/38.0 IP) in 34 relief outings. Dolis held left-handed hitters to a .141 batting average (9-for-64) while right-handed batters hit .388 (31-for-80). With Iowa last season, Dolis went 0-1 with three saves and a 2.51 ERA (4 ER/14.1 IP).
Loe, 31, was claimed off waivers by the Cubs from the Seattle Mariners on April 14. He posted no record and a 5.40 ERA (5 ER/8.1 IP) in seven relief appearances with the Cubs.
Sappelt, 26, batted .178 (8-for-45) in 20 games for the Cubs this season.
Chicago's 40-man roster stands at 40 players.