Chesterfield's plight at the bottom of the Football League deepened after they crashed to a sixth successive league defeat as Morecambe won 2-0 at the Proact Stadium.Adam McGurk scored in each half as former Spireites' goalkeeper Barry Roche made several fine saves to extend the hosts' poor run of just two points from possible 27.Roche denied the home side with a double save from Kristian Dennis and Chris O'Grady in the 11th minute before McGurk fired Morecambe ahead with a 20-yard free-kick six minutes later.Chesterfield were devoid of inspiration until the 42nd minute when Robbie Weir surged forward and beat Roche with a 20-yard strike but his effort came back off the crossbar.But Morecambe extended their advantage two minutes after the restart when McGurk was left unmarked at the back post to head home before Roche made another good save a minute later from Dennis.Dennis was once more denied by Roche, who also blocked a Joe Rowley shot but they could not break down the visitors' defence, who won for the first time in five league matches.