Ally Wollaston overturned a three-second deficit to win the Tour of Britain Women and deny British teenager Cat Ferguson victory.
The New Zealander won all three intermediate sprints on the final stage in Glasgow to draw level with 19-year-old Ferguson, before gaining another four bonus seconds by finishing third behind stage winner Lorena Wiebes and Charlotte Kool.
Wollaston, of FDJ-Suez, beat Movistar's Ferguson by four seconds overall, with UAE Team ADQ's Dutchwoman Karlijn Swinkels finishing third.
"I'm a little bit overwhelmed - sorry. I'm so happy, first of all. A massive 'thank you' to my team-mates, I couldn't have done it without them. This means the world to me - it's my first World Tour victory in GC [general classification]," said Wollaston.
"I knew I needed to get every second I could in the bonus sprints, and unfortunately Cat was right in my wheel every time.
"So it came down to the last sprint, and there was a moment of doubt halfway through that last lap where I thought 'I just cannot do this today'. My team-mates really helped me pull it together and pulled me to the front for the final."
Ferguson looked like claiming the first of three time bonuses for the intermediate sprints at the end of the fourth lap of the 8.4km city-centre circuit, but Wollaston squeezed past her with just metres remaining.
Wollaston then beat the Briton in the second intermediate sprint to trail the overall leader's green jersey by one second.
The 24-year-old moved into the lead with victory on the third intermediate sprint to set up a thrilling finale.
European champion Wiebes launched her attack at the 300m mark before powering over the line first, followed by Kool and Wollaston, who took the last bonus seconds to win the overall classification.
Wollaston's FDJ-Suez also won the team classification, while Ferguson, who finished the fourth stage in seventh, claimed the red points jersey.