The little-known Stal is only featuring at the European Tour's flagship event on the outskirts of London as a late reserve after fellow countryman Victor Dubuisson pulled out with a damaged shoulder at the start of the week.
"I played in honour of my father today," the 22-year-old told reporters on Saturday after signing for a three-under-par 69 in the third round to chalk up a five-under total of 211, 10 strokes adrift of runaway leader Thomas Bjorn of Denmark.
"Tomorrow I will fight for my mother. I will be very aggressive in my play."
Stal, who won the French amateur championship by an eight-shot margin three years ago, secured his 2014 European Tour card at Qualifying School.
He may be making his debut at the BMW PGA Championship but he said his golfing ambitions were always the same.
"Of course I want to win, I will not say otherwise," added Stal. "Each week I'm here to try but we know with golf that's not easy."