Botti Biabi lit up this rivallry after coming off the subs’ bench to set-up Tom Taiwo twice before being red-carded in 21 action-packed minutes.
The 18-year-old laid on both goals but lost the place after becoming involved in a spat with Ross Millen which flared up in the 75th minute.
The pair had been tangling since Biabi’s 54th minute introduction but a move by Millen stepping over - and possibly onto - the substitute sparked a melee and the red card.
Biabi was on the ground when Dunfermline’s number two ran over him and immediately the Academy graduate rolled around clutching his knee. Moments later he was up and in the defender’s face, before moving his head towards the Par who hit the deck immediately.
Referee George Salmond had little option but to send the striker off for his moment of madness, but Biabi’s influence had already given the Bairns the lead.
He came off the bench to lay on both of Tom Taiwo’s second half strikes and send Falkirk into the third round of the Petrovac Training Cup.
The first half was a non-event from A Falkirk perspective, but for Dunfermline it was a puzzler.
Just how could a side who threatened so often with one of the most prolific marksmen in lower league Scottish football, Michael Moffat, pass 300 minutes without scoring?
On quality of chances, Dunfermline should have had the tie sewn up. The best was a shot that Jonathan Page just had to knock into the net from a yard out, but instead he shot it back across goal from a Josh Falkingham free-kick and Jamie MacDonald made an instinctive scoop off the line.
It was an incredible miss but the Pars had played the majority of the first 45 minutes on the front foot and pressuring David McCracken at the back for the Bairns.
In another, said marksman Moffat was front and centre of the goal and steered a cross from El Bakhtaoui wide, unmarked.
Rory Loy was receiving close attention from the Pars but on the occasions he unshackled himself he caused problems - those incidents were like Loy, just too isolated.
In one, he found himself unsupported and raced at the Pars defence missing Gregor Buchanan through injury, and weaving one way then another he zoned in on goal but blasted directly at Ryan Scully.
That was as good as it got for Falkirk though Blair Alston skimmed the crossbar with a 30-yard strike which ref George Salmond awarded a corner for.
But too many passes were going astray for the Bairns, partiuclarly to Alan Maybury on the right side - not always the right-back’s doing. Whether or not it was the pitch or complacency, the trait contoinued in the second half as Will Vaulks misjudged the ball and almost let Moffat in but David McCracken flew across the park to usher the ball out for a throw-in.
Extra-time at the start of the second half was not an attractive prospect with the rain beginning to fall. But that notion turned on the 54th minute, thanks to another substitution by Peter Houston. He pitched in Biabi and Craig Sibbald and both created goals for Tom Taiwo.
First on the 55th minute Biabi relentlessly jockeyed with Ross Millen and cut-back for Taiwo but the ball ran across the midfielder and with a clipped low shot he diverted the ball beyond Scully from 20 yards.
Shortly afterwards it was two, with the subs at the heart of the move, finsihed off by Taiwo. Sibbald moved in a tight space and laid off Biabi who fed Taiwo and it was clipped witht he outside of the midfielder’s boot over Scully and into the net.
Ross Forbes tested MacDonald with a free-kick before the Pars clawed one back through a close-range Andy Geggan header.
Biabi’s red card gave the Pars hope but Falkirk battedned down the hatches, resorting to a 6-2-1 formation in the closing stages, to see out the victory.