Carlisle remain unbeaten in Sky Bet League Two after a 2-2 draw at fellow high-flyers Doncaster.Rovers came from a goal down to lead before Tommy Rowe's missed penalty was punished with a United equaliser.Shaun Miller opened the scoring for the visitors in fortuitous circumstances after he got the final touch on Nicky Adams' wayward shot, just a couple of yards out.That goal should have given momentum to the visitors but it was Rovers who were fired up and they duly equalised two minutes later.A slick, passing move was finished with aplomb by Rowe, who coolly sidefooted the ball into the net.The hosts then dominated play going close on numerous occasions before John Marquis eventually fired them in front from distance.Rowe should have doubled Rovers' lead just after the interval but saw his penalty, won after Andy Butler was felled, come back off a post.Carlisle gradually worked their way back into the game and stretched their unbeaten run thanks to sub Jabo Ibehre's 79th-minute header at the back post.