Mark Prior, sidelined since mid-March with a strained muscle in his right shoulder, will make his first start of the season Sunday for the Cubs in the series finale against the Tigers. "It's just time to go," Cubs pitching coach Larry Rothschild said Saturday. Prior has made four Minor League rehab starts, including a 90-pitch outing Tuesday for Triple-A Iowa. "Mark's pitching [Sunday]," Cubs manager Dusty Baker said. "It's been a long hard road, and I'm glad he's getting back on the mound. I hope we can keep him on the mound all year long."