The hosts raced into a four-goal half-time lead to effectively kill the game as a contest and Colin Daniel's 79th-minute goal was scant consolation.
"We had four balls into our box and they scored four goals," said Simpson, whose side have now gone eight games without a win.
"We made three mistakes and got punished but one or two of the players looked a bit shell-shocked about what had happened and it was another very disappointing night for us."
Source: PA
Source: PA