Chris Froome (Sky) won Tirreno-Adriatico's key mountain stage to Prati di Tivo today and moved within striking distance of the race overall. He trails Michal Kwiatkowski (Omega Pharma-QuickStep) by four seconds.
Froome's win completed a Sky masterpiece. Team-mates Dario Cataldo, Sergio Henao and Rigoberto Urán took control on the final climb. The trio helped control several attacks before Froome fired at the final kilometre.
He caught and passed Alberto Contador (Saxo-Tinkoff), Mauro Santambrogio (Vini Fantini-Selle Italia) and Vincenzo Nibali (Astana). Santambrogio held on for second and Nibali third.
With cold air moving around the ski resort and a light rain falling, Froome celebrated.
"The guys did a fantastic job to get me to the base with the freshest legs possible," Froome said. "I had Dario who worked for a long way, then Rigo and Sergio, the two Colombians, who did a fantastic job, even when the big names, Contador and Nibali attacked, they did their best job to keep me there to win with the freshest legs possible."
Froome trails in the overall by four seconds, but leads Nibali by 12 seconds on Contador and 26 seconds. If he succeeds in three day's time on Italy's Adriatic coast, he would go two for two, winning both races he started this year with Tour of Oman last month included.
Sky created its masterpiece on the 14.5km road that climbed up to the ski station at 1450 metres. The team took over from BMC Racing, who had led to the base of the climb.
Cataldo's pace whittled the lead group down from 50 to 30 riders and pulled in the escapees that had gone free at the second kilometre of he 173km stage from Narni.
Tomasz Marczynski (Vacansoleil-DCM) was the last rider to remain. The Cataldo-led Sky train caught him with 10km remaining. Andy Schleck (RadioShack-Leopard) was already dropped by that point. Samuel Sánchez (Euskaltel) fell back soon after. Cadel Evans (BMC Racing) and Joaquím Rodríguez (Katusha) followed.
"It was a carbon copy of the Tour de France. He just sat calm, waited until the team blew up and then after that he went on his own," Chris Horner (RadioShack-Leopard) explained.
"It's amazing how strong his team is too. It was a block headwind and they had two Colombian guys riding on the front, and it was incredibly hard. It was just incredibly smart and good racing by Sky."
Henao led the race from around 7km out and withstood two attacks by Contador. The triple Grand Tour winner attacked at 6.2km and at 2.7km. Both times, Henao calm rode rhythm until Contador's power faded.
Urán took over following Contador's second attack and drove until Froome went free.
"Froome was in great company and the team worked well for him," Nibali explained. "When Froome went, I waited for Contador to go after him but he didn't have it and Froome won."
Froome now has a fight on his hands with 22-year-old Kwiatkowski. In fact, he is fighting to pronounce his name, having stumbled on the Kw and tk speaking after the stage.
Kwiatkowski finished second overall in his home race, the Tour of Poland last year. In February, he placed second behind team-mate Tony Martin in the Tour of Algarve.
"Tirreno-Adriatico was one of my main goals for the beginning of the season, but I didn't expect I'd take the leader's jersey today with champions like Contador, Froome and Nibali. I didn't think I'd stay with them, but like I said, my team did such a great job and that helps me believe in me and myself," Kwiatkowski explained.
"I will try not to lose time tomorrow or the day after, and then in my speciality, the TT, I will try to gain seconds."
The race continues to Chieti tomorrow, a stage that includes the Passo Lanciano at 1306m and several short and hard ramps leading to the line. After a circuit stage on Monday, Tirreno-Adriatico wraps up with a 9.2km time trial in San Benedetto del Tronto.
Tirreno-Adriatico 2013, stage four: Narni to Prati di Tivo, 173km
1. Chris Froome (GBr) Sky in 4-41-31
2. Mauro Santambrogio (Ita) Vini Fantini-Selle Italia at 6 secs
3. Vincenzo Nibali (Ita) Astana at 11 secs
4. Michal Kwiatkowski (Pol) Omega Pharma-QuickStep at 13 secs
5. Christopher Horner (USA) RadioShack-Leopard at 15 secs
6. Alberto Contador (Spa) Saxo-Tinkoff at same time
7. Rigoberto Uran (Col) Sky at 20 secs
8. Wouter Poels (Ned) Vacansoleil-DCM at 43 secs
9. Joaquim Rodriguez (Spa) Katusha at same time
10. Roman Kreuziger (Cze) Saxo-Tinkoff at 58 secs
Overall classification after stage four
1. Michal Kwiatkowski (Pol) Omega Pharma-QuickStep in 16-04-59
2. Chris Froome (GBr) Sky at 4 secs
3. Vincenzo Nibali (Ita) Astana at 16 secs
4. Alberto Contador (Spa) Saxo-Tinkoff at 30 secs
5. Rigoberto Uran (Col) Sky at 33 secs
6. Christopher Horner (USA) RadioShack-Leopard at 40 secs
7. Mauro Santambrogio (Ita) Vini Fantini-Selle Italia at 40 secs
8. Jonathan Castroviejo (Spa) Movistar at 1-04
9. Roman Kreuziger (Cze) Saxo-Tinkoff at 1-16
10. Joaquim Rodriguez (Spa) Katusha at 1-16
Chris Froome celebrates the stage win
: Race preview and information
Tirreno-Adriatico 2013: Start list
Tirreno-Adriatico 2013: Who will win?
Tirreno-Adriatico 2013: The Big Preview
: Stage reports
Stage three: Sagan beats Cavendish and Greipel
Stage two: Goss wins on wet stage
Stage one: Mark Cavendish leads Tirreno with team time trial win
: Photo galleries
Stage two photo gallery
Stage one TTT photo gallery
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