The Sky Blues may be heading for the fourth tier of English football, being cut 13 points from safety this weekend, but supporters have reason to cheer following a narrow win in the capital.
Coventry got over the line for a rare piece of silverware, however, marking the 30-year anniversary since their famous FA Cup triumph in style.
Bigirimana came close to opening the scoring seven minutes in when volleying wide from the edge of the box, but just five minutes later he had better success after converting from a deflected shot into his path.
The second goal, which ultimately proved to be the matchwinner, arrived 56 minutes in through a fine Thomas strike which flew into the back of the net.
With 15 minutes left to play Lee Burge leapt to deny Chris Maguire, though Sercombe did give Oxford - 27 points above their opponents in League One - a route back into the match by finding a route through a crowded box for his fifth of the season.
There was a tense finish for City as Rob Hall came close to a leveller, but Mark Robins's men survived a late scramble in the box and held on for the trophy, meaning back-to-back defeats in the final for Oxford.