McEwen won a bunch sprint on Sunday

The Davitamon rider held off Olaf Pollack and Paolo Bettini at the end of the 197km (122-mile) stage from Mons to Charleroi in Belgium.

Defending champion Paolo Savoldelli retained the overall race lead after finishing in the same time as McEwen.

Monday's third stage is from Perwez to Namur, with one further stage in Belgium before the race moves to Italy.

"Petacchi saw I was on his wheel and so hesitated in the final 200 metres," McEwen said after Sunday's win.

"Pollack launched the sprint. I was worried about being blocked in and so jumped on his wheel.

"We went past Petacchi and then I squeezed past Pollack close to the barriers and opened up my sprint.

"I won because of my boyhood BMX riding and my 11 years of experience as a professional," added the 33-year-old.

"I make the right decision in eight out of 10 sprints like this one. Of course you still need good legs to win."

Giro d'Italia stage two result:
1. Robbie McEwen (Aus/Davitamon - Lotto) 4 hours 51 minutes 40 seconds
2. Olaf Pollack (Ger/T-Mobile) same time
3. Paolo Bettini (Ita/Quick-Step)
4. Alessandro Petacchi (Ita/Milram)
5. Leonardo Duque (Col/Cofidis)
6. Tomas Vaitkus (Lit/AG2R)
7. Alberto Loddo (Ita/Selle Italia)
8. Koldo Fernandez (Spa/Euskaltel)
9. Maximiliano Richeze (Arg/Panaria)
10. Graeme Brown (Aus/Rabobank)