Sagan, who was pipped to the lined by Mark Cavendish in stage two, had no such difficulties from Cascina to Arezzo. The Cannondale rider sprinted for the line during the final 400 metres, battling it out with BMC Racing Team’s Philippe Gilbert.
The Belgian made a fatal error as he took off too early, allowing for Sagan to catch him through the tight circuit roads and challenging final incline.
Gilbert eventually had to settle for fourth place, with Kwiatkowski and Orica GreenEdge’s Simon Clarke finishing behind winner Sagan.
"I'm really happy to have won," Sagan said.
"As soon as I saw the profile of the stage and finish of this stage I wanted to do well. It went perfectly and I got it. I want to dedicate this stage to my mum, who is not too well at the moment."
"The win is important for me and for the team. I've got to thank my team-mates because they protected me in the final kilometres.
"In the finale I used Bennati's wheel to move back up to the front. I've got to thank him for that. It helped me save energy that I used to produce a good sprint."
Stage three result
1 Peter Sagan (Svk) Cannondale 5:10:17
2 Michal Kwiatkowski (Pol) Omega Pharma - Quick-Step Cycling Team
3 Simon Clarke (Aus) Orica GreenEdge
4 Philippe Gilbert (Bel) BMC Racing Team
5 Daryl Impey (RSA) Orica GreenEdge
6 Daniele Bennati (Ita) Tinkoff-Saxo
7 André Greipel (Ger) Lotto Belisol
8 Simon Geschke (Ger) Team Giant-Shimano
9 Rinaldo Nocentini (Ita) AG2R La Mondiale 0:00:04
10 Lloyd Mondory (Fra) AG2R La Mondiale
1 Michal Kwiatkowski (Pol) Omega Pharma - Quick-Step Cycling Team 9:26:36
2 Rigoberto Uran Uran (Col) Omega Pharma - Quick-Step Cycling Team 0:00:10
3 Simon Clarke (Aus) Orica GreenEdge 0:00:13
4 Tony Martin (Ger) Omega Pharma - Quick-Step Cycling Team 0:00:15
5 Daryl Impey (RSA) Orica GreenEdge 0:00:17
6 Peter Sagan (Svk) Cannondale 0:00:22
7 André Greipel (Ger) Lotto Belisol 0:00:30
8 Daniele Bennati (Ita) Tinkoff-Saxo
9 Luke Durbridge (Aus) Orica GreenEdge 0:00:31
10 Cameron Meyer (Aus) Orica GreenEdge
- Sports & Recreation
- Peter Sagan
- Simon Clarke
- Orica GreenEdge
- Michal Kwiatkowski