Defending champion Chris Froome (Team Sky) was narrowly pipped to victory on stage three at the Tour de Romandie by fellow breakaway rider Simon Spilak (Katusha) as the pair gained 57 seconds on their GC rivals.
Froome launched a devastating solo attack on the final climb to drop rival Vincenzo Nibali, before working in tandem with Spilak to amass a sizable lead in wet and blustery conditions.
Eventually the duo cast aside their allegiance and broke into a sprint duel in the final 300m – the lead swinging back and forth until Spilak made the decisive burst close to the line to snatch victory by a matter of inches.
Spilak heads the general classification by a solitary second from Froome.
Rui Costa led a five-strong chasing pack home nearly a minute later on the 180.2km ride between Le Bouveret and Aigle, which left the Portuguese 62 seconds adrift overall in third and Nibali a further four seconds back.
Stage four results
1. Simon Spilak (Slovenia / Katusha) 5:09:23″
2. Chris Froome (Britain / Team Sky) ST
3. Rui Costa (Portugal / Lampre) +57″
4. Jakob Fuglsang (Denmark / Astana)
5. Benat Intxausti (Spain / Movistar)
6. Mathias Frank (Switzerland / IAM Cycling)
7. Vincenzo Nibali (Italy / Astana)
8. Jesus Herrada (Spain / Movistar) +1:41″
9. Thibaut Pinot (France / FDJ.fr)
10. Andrew Talansky (US / Garmin)
General classification
1. Simon Spilak (Slovenia / Katusha) 11:39:25″
2. Chris Froome (Britain / Team Sky) +1″
3. Rui Costa (Portugal / Lampre) +1:02″
4. Vincenzo Nibali (Italy / Astana) +1:06″
5. Mathias Frank (Switzerland / IAM Cycling) +1:10″
6. Benat Intxausti (Spain / Movistar) +1:13″
7. Jakob Fuglsang (Denmark / Astana) +1:14″
8. Jesus Herrada (Spain / Movistar) +1:40″
9. Jon Izagirre (Spain / Movistar) +1:48″
10. Andrew Talansky (U.S. / Garmin) +1:50″