BRADLEY Wiggins was expecting his Tour de France lead to come under threat on today's 11th stage, when he became the first Briton to wear the yellow jersey for four days in one Tour.
Wiggins' advantage of one minute 53 seconds over defending champion Cadel Evans (BMC Racing) remained intact after the 10th stage, won by France's Thomas Voeckler (Europcar).
The 148km 11th stage from Albertville to La Toussuire -- featuring two hors categorie (beyond category) climbs and ending with an 18km category one ascent -- was set to see further attacks on his hold on the maillot jaune.
"It's the toughest day of the race, so it's going to be a big day," said Wiggins, who was set to succeed the previous best British yellow stint set by Chris Boardman in 1994 and David Millar in 2000.
Keeping the yellow jersey in Paris on July 22 is Wiggins' main goal.
Not only will he have to fend off rivals, but the race leader faces a daily inquisition.
The 32-year-old Londoner on Sunday exploded into an expletive-laden rant when questioned on Twitter speculation regarding drugs.
Questioned again on the spectre of doping in cycling -- an issue relevant due to Remy Di Gregorio's detention by French police yesterday and with the ongoing United States Anti-Doping Agency inquiry into the US Postal team -- Wiggins explained his frustration at being shrouded by suspicion.
Wiggins, whose reply lasted more than two and a half minutes, said: "There's one reason why I'm in this position and that's because I've worked hard and I shouldn't have to justify all that other stuff which we spoke about the other day."
Wiggins crashed out of the 2011 Tour with a broken collarbone, but won the Paris-Nice, Tour de Romandie and Criterium du Dauphine stage races this season and has carried his form into the Tour. He added: "It's not like I've just come from nowhere.
"I've been three times Olympic champion on the track; people have to realise what kind of engine you need to win an Olympic gold medal as an individual pursuiter.
"I've been six times world champion, fourth in the Tour de France, third in the Vuelta last year.
"I'm tested by the UCI (International Cycling Union) God knows how many times a year, God knows how many times on this race and the Dauphine. Blood tested in the morning. What more can I do?"
Ireland's Nicolas Roche finished stage 10 in 14th place, as part of the main peloton, 3:16 behind Voeckler and on the shoulder of Wiggins who was 13th.
Roche's cousin Daniel Martin struggled and came in 90th place over 19 minutes down the time-sheet.
Roche said: "(Today) is a really hard stage, with two hors category climbs and a first category finish atop La Toussire. I know the route well as I've have had numerous training camps there.
"The manager was obviously disappointed that (Jean-Christophe) Peraud didn't finish with the leaders (in stage 10). It's the second day we've had riders in the winning break but they didn't stay -- but the team is very focused around me and hopefully I won't disappoint them over the next few days."