Alberto Contador has already identified Chris Froome and Nairo Quintana as his main rivals for next year's Grand Tours.
The Tinkoff-Saxo rider secured the sixth major win of his career at the weekend, topping the general classification at the Vuelta a Espana for the third time in five years.
The 31-year-old told Spanish sports newspaper Marca: "[Quintana] is very young and he will continue to get better. Perhaps Froome has a point in his favour in the time trial, he is very strong in that discipline.
"In the tough finishes on Farrapona or Ancares [Quintana] would also have been up front, in those more explosive finals, if not both, but now we will not know. It was a shame, but fortunately we will have a chance to see it next year."
Quintana won his first Grand Tour at the Giro d'Italia earlier this year, while Froome and Contador were both forced out of the Tour de France with injury, before the Spaniard got the better of the Team Sky rider in Spain.