The Manxman crossed the finish line on the Luz Ardiden in last place and 32 minutes behind stage winner Tadej Pogačar, but that would've been no concern for him as the main goal of survival had been achieved, two flat stages and the individual time trial now all that separate him from sealing the points classification in Paris.
Cavendish's teammates again made it their sole mission to carry him through the two hors categorie ascents in stage 18 as Michael Morkov, Dries Devenyns, Tim Declerq and Davide Ballerini formed a protective bubble around the 34-year-old right from the start of the course.
But the day wasn't without incident as Team BikeExchange attempted to drop Cavendish on the category 4 Cote de Loucrup just before the intermediate sprint to give second-placed Michael Matthews the best chance to cut into the maillot vert points gap.
That strategy proved unsuccessful as the Manxman managed to hang on through the ascent and sprint to 11 points with Morkov behind him to extend his lead on the Australian to 38 points, revealing the effort left his legs drained with the two climbs still left on the stage.
“That could’ve been a lot easier," Cavendish said of the stage. "But I was already finished before we got to the climbs from doing the intermediate sprint.
"Attacks were going all day on those little categorised climbs and we knew BikeExchange would go on the climb before the intermediate sprint. I burned up so many matches there, just getting to the sprint.
Once the Deceuninck group reached the famous Col du Tourmalet, Cavendish went into full survival mode on the climb he admitted he has a frosty relationship with after 10 years of painful ascents, but had the outstanding support around him to make it bearable.
"Then we got to (Col du) Tourmalet… it’s probably my worst climb in the Tour de France," Cavendish said.
"I’ve done it maybe 10 times and every time I’ve despised it, even before we got to it I was out the back but the lads came around me and paced me over it and through to the finish, I’m so grateful.
"I got a bit emotional after crossing the line because now it seems like all the obstacles are gone to Paris."
An exhausted Cavendish was coy when asked about his prospects of winning stage number 35 to eclipse Eddy Merckx's all-time record, suggesting tomorrow's flat 207 kilometre journey from Mourenx to Libourne may be better for recovery than victory, the first of two chances with the final stage into Paris also likely to put the sprinters in the limelight.
“I don’t know," Cavendish mused when asked if he would contest the sprint in Stage 19.
"If there is I’ll try for one, but it’s 207 kilometres and we’ve had a hard week. I’d like for my boys to be able to sit in the peloton for a bit."
The Tour de France continues with a sprint stage on Stage 19, a largely flat route over 207 kilometres from Mourenx to Libourne. Watch the race on SBS and SBS OnDemand from 2030 AEST, with the race coverage starting earlier on the SKODA Tour Tracker at 2005 AEST.