Steve Plater took victory in an eventful Senior TT at the Isle of Man on Friday, after HM Plant Honda team-mate John McGuinness retired from the lead.
McGuinness, who took his 15th victory in Monday's Superbike TT, looked set to continue his dominance as he pulled a lead of 19 seconds over Plater by the end of lap three of six.
But the Englishman suffered a broken chain on lap four, leaving Plater, second to McGuinness on Monday, with a ten second advantage over McAdoo Kawasaki's Conor Cummins, which Plater built to 19.54sec at the finish.
"I really had it in my head to get a good result and I was all fired up, pushing hard on the out lap as Neil (Tuxworth) has been on at me all week for being an old lady on the first lap!" said Plater. "That's what I was concentrating on and then just seeing how the result went from there.
"It's unfortunate that John went out as he would have been there at the end for sure. I was watching my pit boards as I knew Connor was only about 10 seconds away from me. My Dad was doing my board at Ramsey so he will be desperate to get back now, bless him.
"It seemed like 40 miles from Bungalow down to the finish on that last lap - it was endless. This achievement today will finally sink in next week and then I have to turn my attention back to short circuits and the British Supersport championship.
"I just need a bit of Plater time on my own to take it all in," concluded Steve.
"To be as strong as I was in the race to have to retire due to a broken chain is devastating," admitted McGuinness, who set a new lap record of 131.578mph. "I've won the Senior TT for the last four years and I was going all out to win again today and know that I could have won.
"I felt I had everything in control and inch perfect and the bike was running like a dream. There's nothing else I can say other than I'm gutted for me and also the team and Honda, as it would have been magic to get another 1-2 Superbike race finish with Steve as we did last Monday, especially this year for Honda's 50th. But I'm pleased it was my team-mate to take the top step of the rostrum and at least there's always next year," he added.
Hydrex Honda's Guy Martin was promoted to third by McGuinness's exit, but also suffered a snapped chain and will have to wait another year for his first TT victory.
Padgetts Honda's Ian Hutchinson, who had gained third when Martin retired, fell at the start of lap six, handing the final podium position to Robinson Concrete Honda's Gary Johnson (+70.22sec from Plater).
The start of the race was delayed by 30 minutes due to a rain shower.