The Giant-Shimano rider got the better of Spaniard Vicente Reynes with the finish line in sight.

Overall race leader Michael Matthews of Australia has maintained his advantage by finishing in third place on the 164 kilometres ride from Mairena del Alcor to Córdoba.

A number of riders dropped out of the peloton in today's heat, and it continued to shed numbers over the climbs.

Tinkoff-Saxo, Movistar and Sky had their riders near the front over the final climb as the peloton began to fragment.

After the descent, the peloton reassembled for the final stint, with Sky taking up the pace over the last climb of the race, Alto del Catorce por Ciento.

With nine kilometres remaining, a bunch finish was on the cards, but both Degenkolb and IAM Cycling rider Reynes broke away to duke it out for top honours.

Michael Matthews has held on to the red jersey, and now holds an overall race lead of eight seconds ©AFP/Getty Images



Orica-GreenEdge's Matthews now leads the Vuelta a España by eight seconds from Nairo Quintana of Colombia who rides for Movistar, doubling his advantage of yesterday.

Quintana's team mate Alejandro Valverde of Spain is a further seven seconds behind, with Omega Pharma-QuickStep's Rigoberto Uran of Colombia 19 seconds off the overall lead.

Tomorrow's stage five sees the riders tackle a 180km flat stretch from Priego de Córdoba to Ronda.