There was aggressive racing from the climb of the Madonna del Ghisallo and the very difficult Muro di Sormano that followed it.

Vincenzo Nibali (Astana), who had targeted the race following his expulsion from the Vuelta a España, attacked on the penultimate descent.

Vincenzo Nibali (Astana) came second to Davide Rebellin (CCC–Sprandi–Polkowice) in the Coppa Ugo Agostoni, then won the remaining two races.

[5] The second group was the Trittico di Autunno: these were the Milano–Torino, the Gran Piemonte and Il Lombardia itself, which was the only one of the races to be part of the World Tour.

[8] The race organisers, RCS Sport, also invited eight UCI Professional Continental teams to take part as wildcard entries.

The race took place in Lombardy in northern Italy on 4 October over a course that was 245 kilometres (152 mi) in length, with most of the difficult hills coming in the second half.

After 43.6 kilometres (27.1 mi) the riders reached Entratico, where they joined the main valley road heading north-east.

This was a moderate climb (approximately 3.9 kilometres (2.4 mi) at 4%) and the descent was followed by more flat roads that took the riders north towards Pescate, where they came to the shore of Lake Como for the first time.

Here the course turned gradually back to the south, to pass along the eastern coast of the Lago di Annone and around its southern tip.

The route left the town to the west and climbed the San Fermo della Battaglia (2.7 kilometres (1.7 mi) at 7.2%).

There was a final corner with 600 metres (1,970 ft) to the finish line, which was on the Lungo Lario Trento on the shore of the lake.

As well as performing strongly in the early-season hilly classics in the 2015 season, he had been close to success in Il Lombardia in the past: he finished second in both 2013 and 2014.

"[16] Cycling Weekly suggested that Valverde's ability to recover from the Vuelta in time for Il Lombardia would work in his favour.

[17] Joaquim Rodríguez (Team Katusha) would also have been a strong favourite for the race: he won the 2012 and 2013 editions and had come second in the Vuelta.

[17] Nibali had performed strongly in the other late-season Italian classics, while his team had shown its strength in supporting Diego Rosa to victory in Milano–Torino.

[19] With Rodríguez absent, two other former champions started the race: these were Philippe Gilbert (BMC), the winner in 2009 and 2010, and Damiano Cunego (Nippo–Vini Fantini), who won in 2007 and 2008.

[17] Other favourites for the race victory included Thibaut Pinot (FDJ), Rui Costa and Diego Ulissi (Lampre-Merida), Simon Gerrans (Orica–GreenEDGE), Rafał Majka (Tinkoff–Saxo), Robert Gesink (LottoNL–Jumbo), Warren Barguil (Team Giant–Alpecin), Domenico Pozzovivo and Romain Bardet (AG2R La Mondiale), Michał Kwiatkowski (Etixx–Quick-Step) and Tim Wellens (Lotto–Soudal).

The race began with a succession of attacks; eventually an eleven-rider group escaped to form the day's principal breakaway.

These were Stefan Schumacher (CCC–Sprandi–Polkowice), Enrico Barbin (Bardiani–CSF), Jan Polanc (Lampre-Merida), Matteo Busato (Southeast Pro Cycling), Dennis van Winden (LottoNL-Jumbo), Simon Geschke (Giant-Alpecin), Pierpaolo De Negri (Nippo-Vini Fantini), Marco Canola (UnitedHealthcare), Cesare Benedetti (Bora-Argon 18), Jérôme Coppel (IAM Cycling) and Oscar Gatto (Androni Giocattoli–Sidermec).

The break had a lead that extended to over eight minutes after the Colle Brianza, while the peloton was controlled principally by Astana, with some assistance from Movistar and Team Sky.

Michał Kwiatkowski was the first to attack from the peloton: he was then joined by Matteo Trentin, Carlos Verona, Łukasz Wiśniowski (all Etixx-Quick Step), Tom-Jelte Slagter (Cannondale-Garmin), Jon Izagirre (Movistar), Robert Gesink, Timo Roosen (Lotto NL-Jumbo), Giacomo Nizzolo (Trek Factory Racing) and Tim Wellens.

None of the attacks were successful, as Daniel Moreno (Katusha) brought the other riders back to the leaders, and the group came to the top of the climb together.

Despite almost colliding with a race motorbike at one point, he used his strong descending skills to gain an advantage over the rest of the group.

[11][20] Nibali said after the race that his victory in Il Lombardia made his expulsion from the Vuelta a "good thing" as it helped him find some anger.

[24] Nibali described the victory as being as good as a win in Liège–Bastogne–Liège; he said also that, despite the risks he took on the descent from the Civiglio, Peter Sagan was "crazier" than him when descending.