Spain's Alberto Contador, racing his first cycling Grand Tour since returning from a two-year doping ban last month, won his second Tour of Spain on Sunday.

The Saxo-Bank rider, also a two-time Tour de France winner who lost his 2010 Tour and 2011 Giro titles after testing positive for clenbuterol in 2010, safely negotiated the 21st and final 115km largely flat stage from Cercedilla to Madrid to claim victory.

"This is the culmination of many months of work and sacrifices and not sparing any effort," said Contador.

"People sometimes think it is easy but it is not. I dedicate this victory to those who stuck by me in the good and bad moments. It is because of them that I sacrificed myself."

Contador added: "You feel like laughing, crying, it is a series of emotions that you can't express with words. It is incredible.

"It has been hard from the beginning, but the more things cost you the better they taste. Given the background that I arrived here with, this victory is very special for me. I had not competed for a long time and things were complicated."

Germany's John Degenkolb of the Argos-Shimano team won the final stage in 2hr 44min 57sec, Contador coming through buried in the peloton in 54th spot.

Alejandro Valverde (Movistar) and Joaquim Rodriguez (Katusha) completed an all-Spanish podium after three weeks of racing over 3,300 kilometres.

Valverde was 1min 16sec off Contador's pace, with long-time leader Rodriguez a further 21sec adrift.

Contador had only praise for Rodriguez, saying: "Purito was very strong, he endured the climbs very well.

"It was very hard to win this race but I enjoyed it very much because it was a spectacular Vuelta."

Contador had taken control on Wednesday's stage 17, producing a long-distance attack a day after having failed to shake off Rodriguez on the climb of the Cuitu Negru.

His lead of 1:35 came under attack on Saturday in the gruelling climb of the Bola del Mundo.

But the champion showed all his experience to hold his nerve for a remarkable victory, the Spanish heavyweight trio then called a truce as the sprinters battled for the stage win on Sunday.

A breakaway of six riders were hauled back with one lap of the final 5.7km circuit left, and the Argos-Shimano team managed to get Degenkolb into position for his record-breaking five stage wins on the Vuelta.