Set a daunting target of 272 and starting the third and penultimate day at a dismal 13 for two, Baroda stared defeat in the face at 113 for 6 soon after lunch.
This brought together the Mumbai-born Powar (90 not out, 17X4) and Pathan (81 not out, 11X4, 2X6) who turned the match on its head with their partnership to keep Baroda in the hunt for a semi-final berth.
Powar batted for 287 minutes and faced 186 balls after coming to the crease at the fall of the fourth wicket, that of his skipper Jacob Martin (8).
He went on to stand like a rock and guide his lower order partner Pathan, brother of India pace bowler Irfan Pathan, through a torrid time to frustrate Tamil Nadu.
Baroda, with four points to their kitty from the unexpected win, have taken their points tally to eight with a match in hand, against Uttar Pradesh, to try and qualify for the last four stage behind group leaders Punjab.
Tamil Nadu, who must have entertained high hopes of winning the tie last evening, had to remain content with 11 points with their final league match against Maharashtra at home coming up on December 31.
Brief Score: Tamil Nadu 152 and 183. Baroda 64 and 272 for 6 (Connor Williams 53, Kiran Powar 90 not out, Yusuf Pathan 81 not out; M R Shrinivas 2 for 53, R Ramkumar 3 for 72).