Rangers, then under Mark Warburton, beat Ronny Deila's Hoops on penalties at Hampden Park to reach the showpiece, where they lost to Hibernian.
But the Gers, who were still a Championship side at the time, provided the catalyst for change that has since seen Celtic enjoy domestic domination, originally under Brendan Rodgers.
If the Bhoys - now until caretaker Neil Lennon - beat Hearts in today's Scottish Cup final, they'll have won every single domestic honour since losing to their Old Firm rivals that day - the Treble Treble - and Brown concedes that their defeat by the light Blues left a lot of resentment.
"I remember feeling a little bit jealous that they were in a cup final and we weren't. But Brendan came in and changed our mindset," Brown told The Irish Independent.
"We didn't have a great track record at Hampden before that but he made us realise how to change our mindset, how to improve, how to win.
"While he was here we won seven trophies on the trot. Now Neil's here, we need to make sure we make it nine."
Rangers haven't reached the final of any competition since, despite having three managers in that time.
Steven Gerrard failed to deliver silverware this past season and the pressure is firmly on him to bridge the gap to Celtic's quality next time around. If he doesn't, the fourth managerial appointment of in the post-Warburton era wouldn't be far away.
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