MIAMI— Casey Coleman had a career-high seven strikeouts in 5 2/3 shutout innings Thursday, and the Cubs completed a two-game series sweep by beating the Florida Marlins 5-1. Coleman (2-3) walked five but retired five batters with runners in scoring position and lowered his ERA from 7.22 to 6.03.He departed after throwing 109 pitches, and four relievers completed the eight-hitter, with Carlos Marmol pitching a scoreless ninth. Marmol has thrown 22 2-3 consecutive shutout innings on the road since Aug. 25. Marlon Byrd hit a two-run homer, his third of the season and his second in two nights against Florida. Starlin Castro hit a two-out, two-run double in the ninth, and Reed Johnson doubled home the Cubs first.The Cubs have won their past five games in Miami. They now head to Fenway Park, where they’ll play this weekend for the first time since the 1918 World Series.With Grady Sizemore on the disabled list, Cleveland was also missing DH Travis Hafner for a second straight game with a sore right side and he could be headed to an MRI on Friday. Travis Buck, who was supposed to be the DH, was scratched Thursday with turf toe and replaced by Shelley Duncan.