Team Sky parachuted the Welshman in to race alongside leaders Luke Rowe, Ian Stannard, Gianni Moscon and Dylan Van Baarle in the Hell of the North. It is a chance for Thomas to try the cobbles that will feature in the ninth stage of the Tour and to keep alive his dream of one day lifting the famous cobblestone trophy.
"I love the Classics but I just wanted to concentrate on one thing and do that as best I can," Thomas said of his Tour de France programme.
"That's why I went down the stage racing route but in a few years' time I'd definitely love to be back in the Classics again and racing all the one-days here. It's what I grew up doing and deep down what I love the most."
Thomas could turn back the clock to racing a Classics-only programme after he accomplishes all he wants in stage racing, but for now, the Grand Tours – specifically the Tour de France – is on his plate.
In the last few months, Thomas was trading WhatsApp messages with trainer Tim Kerrison and sports director, and former Roubaix winner, Servais Knaven. Thomas wanted to know if it would fit into his schedule to pop into Paris-Roubaix. Kerrison said yes.
"He was so happy, like a happy kid," Knaven said when Thomas received the green light to drop in for Roubaix.
"I sat down at the start of the year with Tim and tried to figure out the best run-up to the Tour," Thomas continued.
"It was a nice excuse to do this race because of the cobbles in the Tour and use that as a bargaining chip really with Tim but I'm just happy to be here and looking forward to it."
He rode the cobble sectors two weeks ago with Chris Froome to look at the specific ones for the Tour de France stage to Roubaix and again on Thursday, with the Roubaix team. Thomas, as a harsh reminder of the road's dangers, slipped and fell. His left forearm showed the marks.
"That was the misses," he joked. "No, I crashed. It was pretty muddy, but it was just a slip and I fell over."
Even with Thomas's push towards the Tour, he starts in Compiegne as the team's all-star rider with a true chance of winning against favourites Niki Terpstra (Quick-Step Floors), Peter Sagan (Bora-Hansgrohe) and Greg Van Avermaet (BMC Racing).
"It's not a typical build-up to Roubaix. But like I said it's just about getting stuck into the race and taking what I can from it," Thomas continued.
"If you look at the past winners, some of them weren't major favourites coming into the race so a lot can happen as everyone knows.
"I've been in Tenerife and climbing 3500 metres of altitude most days, which is totally different to this race, and I won't necessarily have the punch and stuff that you need for these races, but after 200-odd kilometres not a lot of people to do anyway."
Through bad internet connection on the Tenerife volcano and the occasional look when down at coast at sea-level, Thomas was able to follow the cobbled Classics from E3 Harelbeke, which Thomas won in 2015, through to the Tour of Flanders.
"It's different just watching on TV and the odd results, but Quick-Step obviously looks unbelievably strong and Niki Terpstra is the stand-out rider. Everyone else seems to be on a similar sort of playing field," explained Thomas.
"The usual sort of guys… Everybody seems to be on a decent level but obviously Quick-Step is the standout team.
"We need to sort of ride well as a team, be honest with each other and hopefully one of us is good enough to finish the job. I'll certainly hope to be there in the final and help the guys and maybe take a chance myself."
If Thomas fails to shine in Roubaix, another cobbled experience will serve him well for his ride alongside Chris Froome this July in the Tour de France.
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