The Shrimps boss said: "I was flabbergasted by just how bad we were and I wasn't expecting it to be honest. I have a good set of lads and there are not many times that I have had to have a go at them this season, but they let everyone down."
The result ended Morecambe's return to form after they had won their previous two matches.
Danny Adams returned to the side at left-back at Cheltenham, with Laurence Wilson being pushed forward into a left midfield role, and Mark Duffy dropped to the bench.
McIlroy will now consider changes and has no major fitness concerns, although midfielder Neil Wainwright could remain sidelined due to injury.
Source: Team Talk
Source: Team Talk