The Team Sky rider took control in the eighth stage in 2013 before trouncing his rivals in the mountains and the time trials as Spaniard Contador struggled to find the form that helped him win the race in 2007 and 2009.
Although Froome should receive unprecedented support as the Tour starts in Leeds - the second Grand Depart from Britain in eight years - that will count for little when the event enters France.
Froome will rely on backing from a strong team that includes Geraint Thomas and Bernhard Eisel. Sky have opted to leave out 2012 champion Bradley Wiggins. The defending champion has not had a brilliant season, and his lieutenant Richie Porte has also struggled. Sky have also faced off-road, doping-related allegations that the International Cycling Union (UCI) has yet to clear.
Froome won four stage races in 2013 but this season he has only triumphed in the Tour of Oman and Tour de Romandie and crashed in the last warm-up event, the Criterium du Dauphine, before finishing 12th.
It will be a treacherous Tour for him as it features stretches of cobbled roads in northern France, a tricky crossing of the Vosges mountains and only one time trial - a discipline in which he surpasses all his rivals.
Froome's health has also been a concern as he toiled with a back problem and benefited from a Therapeutic Use Exemption (TUE) to use corticosteroids to treat a chest infection in April, something that was granted by the UCI in controversial fashion.
Contador, who was stripped of his 2010 Tour title after testing positive for a minuscule amount of the banned anabolic agent clenbuterol, must do without key team-mate Roman Kreuziger. The Czech, fifth in last year's Tour, is out of the Tinkoff-Saxo team because he faces a possible UCI investigation into his biological passport data from 2011 and 2012.
Contador, though, seems to be in the form of his life, having beaten Froome in the Dauphine to finish second overall and won the Tour of the Basque country and Tirreno-Adriatico. "Last year he dominated the Tour and there was nothing we could do about it," Contador told the Spanish newspaper As.
"It was a strange feeling being on the podium as winners of the team classification. It's one of the things that motivated me to improve."
Contador has moved from his hometown of Pinto to Switzerland, shifting from quantity to quality in terms of training. Like Froome he will rely on a strong team to help him through the cobbled roads and the mountains.
The fight between the top guns could start before the usual battlefields of the Alps and the Pyrenees as the 10th stage takes the peloton to La Planche des Belles Filles - where Froome took his maiden Tour win in 2012 - with four category-one climbs on the menu.
This is where the outsiders may try to blow the race wide open, a move that was attempted by the Garmin Sharp team last year in the Pyrenees. It will be here that the credentials of Vincenzo Nibali, Bauke Mollema, Juergen van den Broeck, Alejandro Valverde, Andrew Talansky and Tejay van Garderen will be tested.
The absence of last year's runner-up, Colombian Nairo Quintana, takes some of the drama off a race that otherwise promises more thrills than last year. France, who have been waiting for a home winner since Bernard Hinault triumphed in 1985, will follow Thibaut Pinot and Romain Bardet although a top-five finish would be quite an achievement for either.
The battle for the green jersey could go Peter Sagan's way again after the Slovak took it to Paris in the last two editions. Mark Cavendish and Marcel Kittel, who will also have green-jersey ambitions, will probably focus on stage wins a year after the German beat the Briton 4-2.
There will be just four British riders (Froome, Thomas, Cavendish and Simon Yates) compared to last year's six after Wiggins, Alex Howes and David Millar, in his last season, were not picked by their teams.
The Tour pays its respects to those who died in World War One when the peloton goes through Chemin des Dames and Verdun, while women will ride down the Champs Elysees for the first time on the last day as part of a newly-created one-day race.