Colchester played out their second successive 0-0 Sky Bet League Two draw after sharing the spoils with Cambridge.John McGreal's side extended their unbeaten run to six matches with the result, against a Cambridge side who are now undefeated in four themselves.Cambridge went close early on through Uche Ikpeazu but Drey Wright volleyed into the side netting for Colchester soon after and Frankie Kent stabbed wide, as the hosts warmed to the task.Just before the half-hour mark, Wright fired straight at keeper David Forde and then saw a shot fly wide just before half-time.Cambridge's Jevani Brown fired straight at Colchester keeper Sam Walker early in the second half but the hosts had a penalty claim turned down just before the hour after Kane Vincent-Young tumbled under substitute Medy Elito's challenge in the area.Walker dived full stretch to push away Brown's goalbound shot while at the other end, Tom Eastman and substitute Kurtis Guthrie went close for Colchester and Forde pushed away Ryan Jackson's fierce effort, as it ended all square.