Contador, 37, brought down the curtain on a storied career at the 2017 Vuelta – won by Froome – signing off with victory atop the Alto de l’Angliru on the penultimate day of his career.
And Contador says Froome's ability to haul himself back into contention from apparent positions of weakness makes the Briton one of the strangest riders he has ever come across.
"Froome is one of the strangest riders I've ever come across. When he is going up a climb, often he gets dropped early on but, little by little, he fights back," began Contador.
"I remember in Ancares in the Vuelta in 2014, Joaquim Rodríguez attacked, then Alejandro Valverde went for it and I opted to stay with Chris as he fell back behind. First we caught Purito [Rodríguez], then we caught Valverde and a kilometre from the top, I attacked and I could win. It's a very different style to mine, but obviously it gave him some excellent results.
"I remember in the 2013 Tour or Dauphiné I'd attack because I thought he was having an off-day and then he'd end up catching me and dropping me. The first time he did that to me I wasn't so upset, but the second time he turned the tables on me again, I told myself not to fall into the same trap."
The Spaniard won the last of his seven Grand Tour titles in 2015, some five years after the emergence of Team Sky, and Contador, while likening them to football behemoths Barcelona and Real Madrid, adds that they made him a stronger rider.
"This [their financial might] is the same situation as Barcelona or Real Madrid in football. The more money you have, the higher the quality of riders you can buy. It doesn't just depend on that. You've got to have the resources and the right preparation..."
Sky's way of racing forced me to change my training methods; from 2014 I started training at altitude and I got a lot of wins that year.
Froome, of course, is currently recuperating following a heavy crash during a reconnaissance ride for the Criterium de Dauphine back in June 2019 but has targeted both the Tour de France and the Olympics in 2020.