It was the Tykes who had the first half chance of the contest after only six minutes, as David McGoldrick hit an effort wide at the front post.
Meanwhile, down the other end, Scott Banks was able to call Murphy Cooper into action, with the Tykes goalkeeper making a save to his bottom left.
After an underwhelming opening 45 minutes, during which they saw little of the ball, the Seasiders emerged for the restart with a bit more urgency about them.
Despite raising the tempo, clear opportunities still didn’t immediately come the way of Steve Bruce’s side, with Barnsley standing their ground for long periods.
Blackpool’s resilience was eventually rewarded in the 98th minute. Olly Casey played the ball neatly into the feet of Brown, allowing the midfielder to slot past Cooper for the winner.
The result ends a four-game winless streak for the Fylde Coast outfit, and eases the pressure for now following a poor start to the campaign.
Here’s how the Seasiders performed:
1. How did the Seasiders perform?
Blackpool overcame Barnsley at Bloomfield Road. Photo: Gareth Evans
2. Bailey Peacock-Farrell - 6
There wasn't much for Bailey Peacock-Farrell to do between the sticks throughout the game. Photo: Gareth Evans
3. Danny Imray- 8
Like his previous outings, there were some decent bursts forward from Danny Imray, with a number of good balls into the box coming from the right. Photo: Gareth Evans
4. Michael Ihiekwe - 8
It was probably Michael Ihiekwe's best game for Blackpool, with the summer signing looking solid at the back. Photo: Gareth Evans
5. Olly Casey - 8
Olly Casey did his part at the back, clearing everything that came his way, alongside providing the assist for the winner. Photo: Gareth Evans
6. Hayden Coulson - 6
Hayden Coulson gave the ball away cheaply on a couple of occasions in the first half, and was lucky not be punished, but was among those to improve after the break. Photo: Gareth Evans