When GM Alex Anthopoulos set out to upgrade the Blue Jays’ starting rotation this past off-season, Josh Johnson was his primary target. The six-foot-seven right-hander, ace of the Miami Marlins, was the seed from which grew the entire 12-player swap with Miami, remaking the Jays and setting the stage for this highly anticipated season. And coming out of spring training, Johnson looked like he would lead the club’s new-look pitching staff, dealing like the all-star of old. But through the season’s first 2 ½ months, Johnson — much like the Jays themselves — failed to live up to his billing, as his early tenure in Toronto was marked by injury and underperformance. Now, just as the Jays have begun to turn their season around, so has Johnson. On Monday he delivered his finest performance yet, throwing 7.1 shutout innings to lead the Jays to a 2-0 victory over the Colorado Rockies and extend their winning streak to a season-high six games. Johnson left the mound to a standing ovation from the announced crowd of 20,946. “He needed that,” Jays manager John Gibbons said. “He’s looking to bounce back and contribute and I think he felt really good today.” The Jays, in turn, needed Johnson’s best stuff, as they were stymied by Rockies left-hander Jorge De La Rosa, who held them to just one single through his seven innings. Toronto only had three hits on the night, but managed to eke out a pair of runs in the eighth when Rajai Davis led off with a single and stole second, before he and Colby Rasmus moved up on an infield squibber, scoring on a bloop into shallow left field by Maicer Izturis. Southpaw reliever Brett Cecil kept the game scoreless a half-inning earlier when he entered for Johnson with runners at second and third and just one out to face Rockies slugger Carlos Gonzalez, who lined out to Adam Lind. Cecil induced a groundout from Todd Helton to escape the jam and extend his scoreless streak to 16.2 innings. Casey Janssen came on in the ninth to secure his 15th save.