Milan - Dutch rider Bauke Mollema stunned the favourites to cross the line alone on the banks of Lake Como after a spectacular solo break 20km from the finish line in cycling's season-ending Tour of Lombardy on Saturday.
"I can't believe I've won a Monument," said the rider from Groningen who won a stage of the Tour de France in 2017, and the San Sebastian classic in 2016.
Bernal, ten years younger than the winner, settled for a podium finish.
"I think the most important thing is that I'm on the podium and have finished the season well."
Italy's Vincenzo Nibali, a former two-time winner, dropped off the main group at the foot of the Civiglio, one of the toughest climbs, with an average gradient of just under 10 percent.
The Dutch rider then held off late attacks from both Roglic and Valverde in the final descent, to give his Trek team their tenth success this season, after Danish teammate Mads Pedersen won the world road title last month.
"Il Lombardia remains a thorn in my side. It's a race I love but it always escapes me," said the Spaniard.
"But this has been my most successful season and I'm most happy with the fact that I'm finishing the season as number one in the world."