What looked like being a tense top-of-the-table struggle turned on the sending off of Stranraer striker Paul Walker in the 43rd minute as Partick Thistle ran out comfortable winners.
Allan Moore had already grabbed his first goal since joining Thistle turning the ball past keeper Mark McGeown from Danny Lennon's corner.
It was still tight but then Walker was dismissed after the linesman spotted him kicking an opponent. Home keeper McGeown gifted Partick's second allowing a Peter Lindau drive to slip from his grasp and into the net.
Thistle came forward in numbers and Scott McLean sealed an excellent win, firing home from close range after Alan Archibald set him up.