Boonen said that he missed the stage five recon, which includes nine sections of pavé, due to a simple visit to the dentist.
"I was not there because I had to go to the dentist. I had a broken tooth in the Tour of Belgium, which had to be fixed," said Boonen ahead of the Gullegem Koerse on Tuesday. "Anyway, I do not need to do it as I know that route really well."
If Boonen does ride the Tour de France next month it will be his first since 2011, which he abandoned after stage 6 due to injuries he picked up the day before. The Belgian won the points classification in 2007, but has since decided to forgo Grand Tours to focus more on the classics. Boonen's last Grand Tour was the Vuelta a España, also in 2011.
In the past Boonen has indicated that it was unlikely that he would ride the Tour de France ever again. However, the inclusion of the cobbles on stage five spiked his interest in competing this year. The competition for spots will be tough, as the team look to support Mark Cavendish in the sprints and Michal Kwiatkowski in the general classification. Boonen has been in good form recently, with victory in the opening two stages of the Belgium Tour.
With just over a month remaining until the race gets under way in Yorkshire, the final selection is still to be made. "There is nothing yet decided. I just know that I started in Gippingen and then in the Tour of Switzerland."
The Tour de France begins in Leeds on July 5 and finishes in Paris on July 27.
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