Froome (Sky) finished runner-up to Aru (Astana) on the featured uphill finish with Alejandro Valverde (Movistar) rounding out the podium. The Sky leader collected time bonuses during and at the end of the stage to lessen the gap to race leader Alberto Contador (Tinkoff-Saxo), who he now trails by one minute and 19 seconds.
The peloton was reluctant to let any moves go at the beginning of the race that featured two ascents of the category two Monte Castrove in the final 30km of what was a circuit finish. Eventually Luis Leon Sanchez (Caja Rural - Seguros RGA), Johan Le Bon (FDJ.jr) and Hubert Dupont (AG2R La Mondiale) escaped but were inevitably caught with a stage win available for the general classification contenders. Sanchez was the last to be caught, with Sky doing the majority of the chase work on the front of the main group, with some 15km remaining.
The main stage and race contenders stayed together in the front group toward the business end of the race. Aru, who started the day fifth overall, moved across to Jerome Coppel (Cofidis) within the last 4km and, unlike the latter, never looked back.
Coppel dropped as Contador's Tinkoff-Saxo took to the front with Aru holding a slender 11 second advantage. Froome made his key move inside the last 2km leaving Contador, Valverde, plus others, in his wake to bridge to Aru.
However, the 2013 Tour de France champion could not match Aru in the sprint to the finish line and had to settle for second in a day that he can be pleased with, with Sky again demonstrating its trademark control throughout.
Meanwhile, Fabian Cancellara (Trek), Tom Boonen (Omega Pharma - Quick Step), Robert Gesink (Belkin), Koen de Kort (Giant-Shimano) and Cameron Meyer (Orica-GreenEdge) were among several riders that did not start the 18th stage. Cancellara, Boonen and Meyer all cited preparation for the upcoming UCI Road World Championships. Gesink had a private family matter to see to and de Kort withdrew due to illness.
Vuelta a Espana 2014, stage 18: A Estrada to Monte Castrove en Meis, 157km
1. Fabio Aru (Ita) Astana 3-47-17
2. Christopher Froome (GBr) Team Sky
3. Alejandro Valverde (Spa) Movistar at 13secs
4. Joaquin Rodriguez (Spa) Katusha
5. Alberto Contador (Spa) Tinkoff-Saxo
6. Samuel Sanchez (Spa) BMC at 17secs
7. Daniel Navarro (Spa) Cofidis at 33secs
8. Daniel Moreno (Spa) Katusha at 48secs
9. Damiano Caruso (Ita) Cannondale
10. Warren Barguil (Fra) Giant-Shimano
Overall classification after stage 18
1. Alberto Contador (Spa) Tinkoff-Saxo in 71-38-37
2. Christopher Froome (GBr) Team Sky at 1-19
3. Alejandro Valverde (Spa) Movistar at 1-32
4. Joaquin Rodriguez (Spa) Katusha at 2-29
5. Fabio Aru (Ita) Astana at 3-15
6. Daniel Martin (Irl) Garmin-Sharp at 6-52
7. Samuel Sanchez (Spa) BMC at 6-59
8. Warren Barguil (Fra) Giant-Shimano at 9-12
9. Daniel Navarro Garcia (Spa) Cofidis at 9-44
10. Damiano Caruso (Ita) Cannondale at 9-45
Belkin team leader Robert Gesink withdraws from Vuelta a Espana to be with pregnant wife after she undergoes surgery
German sprinter John Degenkolb takes bunch sprint; Alberto Contador remains in overall lead
"Rodriguez turned towards me and punched me full in the face" says Sky's Philip Deignan
Chris Froome attacks on final climb but cannot shift Alberto Contador from top of general classification
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