Lizzie Armitstead continued her dominant start to the season by winning the Tour of Flanders one-day classic in Belgium on Sunday.
The 27-year-old Briton escaped from the peloton alongside Emma Johansson with just over 16km remaining and then defeated the Swede by half the width of a wheel in a sprint finish in Oudenaarde.
It was Armitstead's fourth win from her six races so far this year and sees her return to the top of the UCI Women's WorldTour rider rankings.
She said: "It was a really strange race with just two in the front. We had to commit. I didn't leave anything for the sprint. Emma is fast and I didn't underestimate her.
"It was a poker game in the end. I didn't have any radio, so I didn't know what was happening."
The Tour of Flanders is one of the most prestigious races in women's cycling and has been a key target for Armitstead in recent years. Her previous best result had been second in the 2014 edition.
Johansson (Wiggle-High5) initiated the decisive breakaway by attacking shortly before the final climb of the day and Armitstead (Boels-Dolmans) was the only rider to follow.
They opened up a lead of more than 20 seconds, but a chase group of eight cut that to less than 10 seconds going into the final 1km and it briefly looked like the front two would be caught.
However, Armitstead set a pace high enough to keep the chasers at bay and although Johansson made her lead out the sprint, the reigning world champion had just enough power left to snatch a narrow and hard-earned triumph.
The chasers finished two seconds later, with Chantal Blaak (Boels-Dolmans) winning the sprint for third place.
Armitstead is now 25 points ahead of Blaak at the top of the UCI Women's WorldTour rankings on 368 points after five of the series' 17 races.
Result
1 Lizzie Armitstead (GB) Boels-Dolmans, 3:53:38
2 Emma Johansson (Swe) Wiggle-High5, same time
3 Chantal Blaak (Ned) Boels-Dolmans, +2sec
4 Megan Guarnier (USA) Boels-Dolmans, st
5 Elisa Longo Borghini (Ita) Wiggle-High5, st
6 Ellen van Dijk (Ned) Boels-Dolmnans, st
7 Annemeik van Vleuten (Ned) Orica-AIS, st
8 Pauline Ferrand-Prevot (Fra) Rabobank-Liv, st
9 Claudia Lichtenberg (Ger) Lotto Soudal, st
10 Katarzyna Niewiadoma (Pol) Rabobank-Liv, +8