Bartolo Colon was dealing with a back issue in his last start, a Mets source confirmed to the Daily News Tuesday night, and “it remains to be seen,” if he will be able to make his next scheduled start on Saturday. The 40-year-old pitcher was shelled by the Angels giving up back-to-back-to-back home runs in the first inning. In an very uncharacteristic performance by Colon, he lasted just five innings, gave up nine runs on 11 hits in the loss to the Angels. “It was a factor, yes,” the team source said when asked if Colon’s back affected his performance.