The Irishman attacked a select lead group within the final kilometre to take the victory from Alejandro Valverde (Movistar) in second and Rui Costa (Lampre-Merida) in third.
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Martin’s win was a convincing one after a year of disappointment that saw his chances of winning Liege-Bastogne-Liege in the spring evaporate after a badly-timed crash on the race’s final bend. He then crashed out of the Giro d’Italia in May when the race started in Belfast, not even completing the opening team time trial stage.
Michal Kwiatkowski (Omega Pharma-QuickStep) endured bad luck during his first outing in the World Champion’s jersey, suffering from cramp in the final 10 kilometres and rendering himself unable to contest the finish.
It was a momentous occasion for Australian Cadel Evans (BMC Racing), as he took part in his final European race before retiring early next season.
With yet another second place, Valverde now moves back into the lead in the UCI WorldTour ranking with just the Tour of Beijing remaining.
Tour of Lombardy 2014, 256km
1. Daniel Martin (Irl) Garmin-Sharp in 6-25-33
2. Alejandro Valverde (Spa) Movistar at 1 sec
3. Rui Costa (Por) Lampre-Merida
4. Tim Wellens (Bel) Lotto-Belisol
5. Samuel Sanchez (Spa) BMC Racing
6. Michael Albasini (Swi) Orica-GreenEdge
7. Philippe Gilbert (Bel) BMC Racing
8. Joaquim Rodriguez (Spa) Katusha
9. Fabio Aru (Ita) Astana
10. Rinaldo Nocentini (Ita) Ag2r La Mondiale at 14 secs
We pick out the leading contenders for this year's Il Lombardia, which takes place on Sunday October 5
Full preview for Il Lombardia 2014: info, route, profile, TV guide, past winners and more