Boonen cruised across the line more than a bike- length ahead of his closest rival, Thor Hushovd of Norway, to take the third and most comfortable Tour stage win of his career.
Boonen's relief on clinching victory was palpable. In 2004 he took more than a week to win a Tour stage - far too long for the Belgians, well aware of their status as cycling's leading nation but now into their third decade without a potential overall contender for the race.
"It's good to get this [stage win] off my chest." Boonen said yesterday. "Now I can relax a bit and avoid so much pressure." Two days before the Tour got under way, however, the Belgian had got something else out of his system - an infected molar tooth in his lower right jaw.
"It was very, very painful." Boonen admitted. "I had thought of not starting the race at all, but fortunately we could find a dentist in time."
Yesterday's 181.5km stage was designed for the sprinters, cutting a broad but not excessively hilly semi-circular swathe through the Vendée region, one of France's cycling heartlands.
There were few opportunities for the locals to shine, but Thomas Voeckler, who led the Tour in 2004, took advantage of the one classified climb of the day, a short ascent close to the finish, to seize the first points on offer for the King of the Mountains classification.
Voeckler would be the first to admit the polka-dot jersey he therefore donned after the stage does not have the same prestige as the maillot jaune he stoutly defended for 10 days last summer.
However, it was still a gesture appreciated by his team, Bouygues Telecom - their headquarters are a stone's throw from yesterday's finish line.
Voeckler earned a spot on the podium thanks to him taking part in a four-man break which - thanks to his presence - earned huge cheers from the public lining the route as the quartet attempted, unsuccessfully, to fend off the chasing peloton, led by Boonen's team workers.
The Salt Lake City-born Dave Zabriskie, currently leading the race, did not spark as enthusiastic a response from the crowds, but there was no questioning his right to the yellow jersey.
Gifted with a fine sense of humourous understatement - "I rode my bike" was his response to press questions as to how he had spent his first day as race leader - Zabriskie is also clearly an immensely talented time triallist, as he showed on Saturday when he won the Tour's opening stage by two seconds over the favourite, Lance Armstrong.
Although he had aimed to take the yellow jersey from the first day, Armstrong had reason to be satisfied with Saturday's performance. In just 19km, the six-times Tour winner managed to gain a 66-second advantage over his arch-rival Jan Ullrich, underlining his strength by overtaking the German, who had started a minute before, close to the finish line.
Tomorrow's team time trial is Armstrong's first opportunity to return to yellow but beforehand, on today's flat 200km run to Tours, there is another prospect of a bunch sprint. Boonen, having got his teeth into one victory, will surely be up for second helpings.
Alasdair Fotheringham writes for Cycling Weekly
Results from stages one and two
Stage One (19km, Fromentine to Noirmoutier-en-l'Île): 1 D Zabriskie (US) Team CSC 20min 51sec; 2 L Armstrong (US) Discovery Channel +0.02sec; 3 A Vinokourov (Kaz) T-Mobile Team +0.53; 4 G Hincapie (US) Discovery Channel +0.57; 5 L Bodrogi (Hun) Crédit Agricole +0.59; 6 F Landis (US) Phonak Hearing Systems +1min 02sec; 7 F Cancellara (Swit) Fassa Bortolo same time; 8 J Voigt (Ger) Team CSC +1.04; 9 V Karpets (Rus) Illes Balears-Caisse d'Epargne +1.05; 10 I Gonzalez de Galdeano (Sp) Liberty Seguros-Wurth +1.06; 11 B Julich (US) Team CSC +1.07; 12 J Ullrich (Ger) T-Mobile Team +1.08; 13 J Enrique Gutierrez (Sp) Phonak Hearing Systems +1.12; 14 L Leipheimer (US) Gerolsteiner +1.13; 15 M Rich (Ger) Gerolsteiner +1.16; 16 J-L Rubiera (Sp) Discovery Channel s/t; 17 Y Popovych (Ukr) Discovery Channel +1.18; 18 B McGee (Aus) Française Des Jeux +1.24, 19 M Wauters (Bel) Rabobank +1.25, 20 I Basso (It) Team CSC +1.26.
Stage Two (181 km, Challans to Les Essarts): 1 T Boonen (Bel) Quick-Step 3hr 51min 31sec; 2 T Hushovd (Nor) Crédit Agricole s/t; 3 R McEwen (Aus) Davitamon-Lotto; 4 S O'Grady (Aus) Cofidis; 5 L Pagliarini (Br) Liquigas; 6 J Antonio Flecha (Sp) Fassa Bortolo; 7 P Wrolich (Aut) Gerolsteiner; 8 J Pineau (Fr) Bouygues Telecom; 9 B Cooke (Aus) Française des Jeux; 10 A Davis (Aus) Liberty Seguros all s/t; 11 M Quinziato (It) Saunier Duval) +5sec; 12 R Hunter (SA) Phonak; 13 I Isasi (Sp) Euskaltel; 14 Y Krivtsov (Ukr) AG2R; 15 A Furlan (It) Domina Vacanze; 16 M Iglinskiy (Kaz) Domina Vacanze; 17 S Hinault (Fr) Crédit Agricole; 18 A Geslin (Fr) Bouygues Telecom; 19 J Ullrich (Ger) T-Mobile; 20 F Rodriguez (US) Davitamon-Lotto) all s/t.
Leading overall standings: 1 D Zabriskie (US) Team CSC 4hr 12min 27sec; 2 L Armstrong (US) Discovery Channel +2sec; 3 L Bodrogi (Hun) Crédit Agricole +47; 4 A Vinokourov (Kaz) T-Mobile +53; 5 G Hincapie (US) Discovery Channel +57; 6 F Landis (US) Phonak +1min 02sec; 7 F Cancellara (Swit) Fassa Bortolo; 8 J Voigt (Ger) Team CSC +1:04; 9 V Karpets (Rus) Illes Balears +1:05; 10 I Gonzalez de Galdeano (Sp) Liberty Seguros +1:06.
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