The 34-year-old took what was his fourth victory of the season by overcoming a strong Dimension Data squad at the 162km race. Impey set off alone in pursuit of Nic Dlamini on the final lap of the race, catching and dropping the Dimension Data rider to solo home for the win 25 seconds ahead of Dlamini's teammates Ryan Gibbons and Stefan de Bod, who took third, another six seconds back.
"I just wanted to fight for it," Impey said on his team's website of his numerical disadvantage. "Win, lose or draw, I wanted to go all in.
"Even though they threw everything at me, I rode intelligently and used my experience because I have been in this situation many times," he said, having started the race as the only Mitchelton-Scott representative.
"I didn't think I'd be taking the jersey back to Europe just because I had the odds against me," Impey continued, "so it just shows you it's never over till it's over. I'm backing myself more, and it's a great step forward in my career."
"I had massive support from my family and friends. History made again," he said, having taken his record eighth TT title in a row on Friday. "I love doing the double."