Late goals from Declan McManus and Ross Caldwell helped Morton to a 3-1 win at Peterhead that kept them in touch with leaders Stranraer.McManus struck with three minutes left before Caldwell scored deep into stoppage time.In the first half, Morton goalkeeper Derek Gaston had to make fine saves from Kevin Dzierzawski and Andrew Rodgers while McManus and Conor Pepper could not hit the target at the other end.Peterhead took the lead 11 minutes after the break when Sean Crighton fouled Rodgers in the area and the striker stepped up himself to score.McManus scored his first just after the hour mark, slotting past Smith after being set up by Ross Forbes, and added his second when Caldwell unselfishly squared for him to tap in.And Caldwell rounded things off four minutes into added time, taking McManus' pass to fire home.