Two-goal Stern John prayed in the Saints dressing room while his teammates hung on without him.
The Saints hero gave his club a 53rd-minute lead from Marek Saganowski's excellent pass before netting his stylish 69th-minute winner.
But having been booked for taking his shirt off while celebrating his first goal, he was sent off after receiving a second yellow card for a late tackle on Sheffield United defender Derek Geary in the 80th minute.
"I was in the dressing room on my knees while watching the last ten minutes on television!" he said.
"It's been a rollercoaster season and today was very emotional for everyone.
"For the neutral it must have been fantastic.
"When we went 1-0 down against the run of play we were battering them but we showed resilience, character and stayed focused."
The Trinidadian feared his decision to remove his shirt in front of the Chapel Stand would prove costly while United laid siege to Richard Wright's goal during the closing stages.
"I don't think the referee was going to book me when I took my shirt off but the linesman called him over," he said.
"I broke the rules and I hold my hands up but it was emotional for me.
"I wanted to celebrate and the adrenaline took over.
"The last ten minutes were really nailbiting for us.
"It was a silly striker's tackle, it was my first of the season so the lads gave me plenty of stick for it afterwards.
"I'll have to watch my timing next time!"
Full story and 16-page football special with all the drama and emotion from St Mary's in today's Daily Echo.
