Bruce Anstey snatched victory in the Supersport 1 race by just 0.77 seconds this afternoon.
The Kiwi managed to hold off Cameron Donald to take his ninth victory around the Mountain Course.
William Dunlop finished third, his first podium at the TT.
Earlier in the race William's younger brother Michael dominated, opening up a 20-second lead by the end of lap two and recording a new lap record in the process.
But mechanical problems forced him to retire at Ballig Bridge.
The man who took over at the front, Gary Johnson, maintained a slender lead over Anstey and Donald until he too was beset by mechanical problems over the Mountain section on the final lap.
That left the way clear for Anstey, who did just enough:
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