The Cubs are moving Travis Wood out of the rotation and into the bullpen.
Wood has struggled to the tune of a 5.59 ERA and 1.29 WHIP as a starter this season.
After a 3.04 ERA in four April starts, Wood carries a 10.13 ERA in May, surrendering 15 earned runs and six homers in 13.1 innings across three starts.
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Wood was an All-Star in 2013, accounting for 200 innings with a 3.11 ERA and 1.15 WHIP. But he took a step back last season, going 8-13 with a 5.03 ERA and a 1.53 WHIP.
Japanese lefty Tsuyoshi Wada is expected to join the rotation in Wood's place, but no official word will be made until Sunday.
The Cubs signed Wada to a one-year, $4 million deal in the offseason, but the 34-year-old starter was placed on the disabled list with a groin injury to start the season. His last rehab start was Thursday with Triple-A Iowa.
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Wada impressed in 13 starts down the stretch for the Cubs in 2014, going 4-4 with a 3.25 ERA and 1.24 WHIP. He initially signed with the Orioles out of Japan, but his career in Baltimore was derailed by arm injuries, including a Tommy John surgery in May 2012.
Wood appeared in relief Saturday and picked up his first career save, working a perfect ninth inning.