The 32-year-old Welsman needs to preserve a lead of two minutes and five seconds in today’s final test to ensure tomorrow’s final sprint stage into Paris is a triumphant procession.
Typical of his performance over the last three weeks, the Team Sky rider repelled every attack any of his general classifications rivals made before sprinting away from them in the final 100 metres of a brutal 19th stage to finish second and claim the six-second time bonus.
It was yet another example of his complete dominance of the race since winning stage 10 last Tuesday week.
“I’m not taking anything for granted,” said Thomas last night. “I just want to get out there and do the best ride I can. It’s nice to have that buffer. I don’t have to take any risks but I’ve still got to get through it.”
Thomas’s team-mate and the defending champion, Chris Froome, dropped out of the podium places because of Primoz Roglic’s stage win.
Thomas’s closest challenger remains Dutchman Tom Dumoulin, who also happens to be the world time-trial champion, and is therefore favourite to win today’s stage and take time off Thomas.
But Thomas’ own pedigree in time-trials should not be overlooked after he won the British title in June.