Managerless Stockport saw their plight worsen as former Manchester United striker David Healy bagged his first hat-trick for Preston during a 6-0- rout at Deepdale.
The bottom-of-the-table visitors, after Andy Kilner's midweek departure, had Jason Van Blerk dismissed for throwing a punch at defender Graham Alexander to leave them with an impossible task.
Stockport were torn apart early on when Colin Murdock's 11th-minute tackle on Scott Taylor allowed him to release Healy. The 22-year-old played a one-two with Paul McKenna before firing into the back of the net for the opener.
County never recovered from that early blow and Alexander evaded the challenge of two defenders to squeeze a ball out to Healy who seized his chance to fire past ex-England goalkeeper Tim Flowers.
Then Van Blerk heaped more misery on his Stockport team-mates, lashing out at Alexander in frustration having been denied a free-kick.
With Stockport battling on with 10 men, Healy's third arrived on 37 minutes courtesy of a sharp header.
In first-half injury time, striker Scott Taylor set up Glynn Hurst who raced towards goal as Stockport threatened for the first time only for replacement goalkeeper David Lucas coming to collect.