Rolison will serve as the Cubs' opening pitcher for Sunday's game against the Giants in San Francisco, Vinnie Duber of the Chicago Sun-Times reports.
Rolison has been an effective relief option this season with a 2.25 ERA, 1.25 WHIP and 24:12 K:BB over 24 innings, and he's now set to make his first start of the season and the second of his MLB career. The left-hander has covered more than one frame in eight of his 20 appearances with Chicago and is likely to give way to Colin Rea after working an inning or two Sunday.