With the game drifting towards defeat, Dortmund were again able to rely on their young brigade, with Bynoe-Gittens and 17-year-old Youssoufa Moukoko scoring two quick goals to see the visitors pick up a valuable three points in their quest for a sixth Bundesliga title.
Dortmund manager Edin Terzic lauded his side’s depth and praised “game-changer” Bynoe-Gittens.
“With him, it’s pretty simple – he’s got the skills to decide games,” said Terzic.
“He’s a game-changer and (I told him when he came on) I wanted to see that from him.
“We fought back, scored three goals through three substitutes and showed how good the squad is.”
The visitors dominated the early stages, with Anthony Modeste – playing in his first game for Dortmund just days after transferring from FC Cologne – striking up an immediate partnership with captain Marco Reus.
Reus teed up Modeste to run into the left side of the penalty box in the 20th minute, forcing Freiburg keeper Mark Flekken into a save.
Modeste also had a chance right in front in the 32nd minute after superb one touch football from Jude Bellingham and Raphael Guerreiro, but the Portuguese’s cross was inches too high.
As if stunned into action, Freiburg then flipped a switch, building pressure on a suddenly shaky Dortmund defence.
Roland Sallai won a free kick on the edge of the box with 33 minutes played.
Dead-ball specialist Vincenzo Grifo stepped up to force a fingertip save from Gregor Kobel in goal.
Freiburg took the lead minutes later, when former Dortmund defender Matthias Ginter found Michael Gregoritsch who deftly drifted a header over Kobel and into the top right corner of the goal.
– Dortmund turns to youth –
Terzic turned to youth halfway through the second half, bringing on Bynoe-Gittens and Moukoko to introduce some potency to Dortmund’s attack.
Known more for his dribbling and assists, the Englishman equalised with a stunning strike from outside the box.
While his shot was helped by a poor attempted save from Freiburg keeper Mark Flekken, the goal spurred Bynoe-Gittens and Dortmund into action
The former Manchester City academy player had a chance to put his side in front after 82 minutes, but was unable to control a sharp Marius Wolf pass with the goal begging.
He then set up Dortmund’s second just a minute later when he slalomed past several Freiburg defenders on the edge of the area before delivering a no-look pass to Julian Brandt.
Brandt, who had also been brought on by Terzic in the second half, found Moukoko in the box, with the teenager whipping in from close range.
Wolf, another who was subbed on in the second half, then put the result beyond doubt in the 88th minute, striking powerfully across goalkeeper Flekken and into the bottom left corner of the net.
The game was manager Terzic’s ninth win in a row in charge of Dortmund, breaking a record set by former mentor Juergen Klopp a decade ago.
The loss continues a poor run of home form for Freiburg recently, with the Breisgauer now conceding 16 goals in their last six games at Europa Park Stadium.
Despite the loss, Freiburg manager Christian Streich said he was impressed by his side’s “unlucky” performance.
“We played a good game, I’m satisfied,” he said.
“Ultimately we lost, it’s a shame… but it doesn’t achieve anything to think we were unlucky to lose the game.”