In a marathon month sprinkled with Dublin derbies perhaps it was inevitable that this EA Sports Cup quarter-final went the distance.
Ultimately, Shamrock Rovers prevailed as goalkeeper Reyaad Pieterse saved from James Chambers and Ian Daly.
Gary McCabe, Stephen O'Donnell, Gary Twigg and Conor McCormack converted the Rovers spot-kicks and while Seanie O'Connor and John Russell netted for St Patrick's Athletic, Pieterse emerged as the unlikely Hoops hero.
It was a highly competitive clash throughout with referee Damien Hancock issuing nine yellow cards. Though Rovers were sluggish for vast chunks of a first half ruled by Pat's, the Hoops hit the front in the sixth minute.
Aidan Price had his pocket picked by Killian Brennan and the Pat's defender was yellow-carded for a foul on the winger. Brennan curled a splendid 22-yard free-kick around the Saints wall and in.
Surprisingly, Rovers were then frustrated by their hosts. Liam Buckley's favoured 4-3-3 formation ensured the Saints had an extra body in the centre of the park and Pat's enjoyed plenty of possession, but had to wait until the 27th minute until parity was restored.
John Russell scampered down the right flank and fed Pat Flynn, who crossed for O'Connor at the back post. O'Connor's header looped over Pieterse.
After the restart the encounter followed a similar pattern with Pat's probing as Greg Bolger went close with an effort from outside the area, but then Rovers upped the ante.
Gary O'Neill was denied by a Barry Murphy save, while Price made a great block to thwart Aaron Greene. It stayed tight and tense until the end of extra-time, but Pieterse earned the shoot-out glory.
The South African had some shaky moments, but two excellent reflex saves from Chambers and Daly proved decisive.