Alejandro Valverde narrowly held off the chasing peloton to claim an impressive win at the Italian one-day race Roma Maxima.
The Movistar rider escaped from a severely thinned-down front bunch alongside Domenico Pozzovivo around 37km from home and the duo looked to have built up enough on an advantage to hold on and sprint for the win between themselves.
However, a replenished peloton came back at them strongly in the final 3km and although Ag2r-La Mondiale's Pozzovivo was caught, Valverde had just enough energy left to sprint to victory by about 10 metres in the shadow of Rome's Colosseum.
Davide Appollonio (Ag2r-La Mondiale) snatched second place ahead of Sonny Colbrelli (Bardiani-CSF) in third, with Pozzovivo missing out on the podium in fifth.
Valverde's victory was his sixth of the season following a spree of wins at the Ruta del Sol and Vuelta a Murcia in recent weeks, and came just 24 hours after he finished third at Strade Bianche.
He said afterwards: "I'm super happy, it was a great victory. It all went perfectly for us, but we deserved it. The team was sensational and took control of the race all day, so we could get to the climbs with all chances to succeed.
"Eventually, I went away with Pozzovivo. Though I led the first part of the descent, he helped me out quickly and was a loyal break companion. It is sad he couldn't take second, because he deserved to be on the podium."
The 195km race started and finished in the Italian capital and came to life around 40km from home, when Valverde and team-mate Nairo Quintana forced hordes of riders to be dropped out of the peloton by exchanging attacks on the lower slopes of the Campi di Annibale climb.
Only about 25 riders remained at the head of the race when they hit the steepest part of the ascent, and soon Pozzovivo, a diminutive climbing expert, started to ride clear on his own as those around him wilted on the sapping gradient.
Valverde managed to ride back on to the Italian's wheel and the duo took a lead of more than 20 seconds over the summit, which they then stretched to more than 30 seconds on the descent down the other side.
With the group behind looking increasingly disorganised, it seemed certain that gap would be enough to see them safely to the finish, but the chase swelled in both numbers and urgency in the closing stages, setting up a tense and thrilling finale.
1 Alejandro Valverde (Spa) Movistar, 4:45:45
2 Davide Appollonio (Ita) Ag2r-La Mondiale, same time
3 Sonny Colbrelli (Ita) Bardiani-CSF, st
4 Antonio Parrinello (Ita) Androni Giocattoli, st
5 Domenico Pozzovivo (Ita) Ag2r-La Mondiale, st
6 Alessandro Bazzana (Ita) UnitedHealthcare, st
7 Jarlinson Pantano (Col) Colombia, st
8 Philippe Gilbert (Bel) BMC, st
9 Simon Geschke (Ger) Giant-Shimano, st
10 Mauro Finetto (Ita) Yellow Fluo, st