Arcalis - Tour de France leader Chris Froome said he spent the final climb of Sunday's Pyrenean mountain stage waiting for an attack from Nairo Quintana that never came.
With two-time former champion Alberto Contador abandoning the race through injury and illness during the 184.5km ninth stage that started in blazing hot sunshine in Spain and finished in hail and rain in Andorra, Quintana is widely considered to be Froome's closest challenger.
The Colombian finished second to Froome in each of the Briton's previous Tour victories in 2013 and last year.
But Froome, 31, was surprised the Movistar leader never launched an attack on the 10km climb to Arcalis.
"In the back of my mind I was waiting for his attack all the way up to the last kilometre," said Froome.
"Into the last kilometre I thought, 'he hasn't attacked yet, maybe he's waiting for one big move'. But it never came.
"I'd like to think he was on the limit. It was a tough day out there but it just looks like he stuck to my wheel like glue."
Quintana's Movistar team-mate Alejandro Valverde defended his leader.
"Nairo did well to hang in there with Froome," he said.
"Is Froome unrivalled? Nairo is too. There's a long way to go left in the Tour, you must attack when you must attack.
"Nobody knows when that might be."
In his previous two Tour challenges, Quintana, 26, has always lost time in the first week before coming on strong in the third and final week.
Last year he lost time to Froome in the Pyrenees before gaining back more in the Alps, losing out in the end due to time he gave up on a cobbled flat stage.
This year he's lost only 23 seconds in the Pyrenees from Froome's daring downhill attack on Saturday's eighth stage.
The overall standings remain extremely tight with the top nine riders separated by less than a minute.
Quintana is fourth with Briton Adam Yates second at 16sec and Dan Martin of Ireland third at 19sec.
Both of those, along with Australian Richie Porte, crossed the line with Froome and Quintana.
"I've said it a few times coming into this race, I feel this is going to be the biggest battle of my career, and that's what it's turning out to be," said Froome.
"The level is higher and I'm going to have to fight for every second I can."
One rider who is not yet ready to challenge Froome for overall glory is ninth stage winner Tom Dumoulin of the Netherlands.
Known as a time-trial specialist, Dumoulin showed he has more strings to his bow than just that by winning such a tough mountain stage.
"I still have to make another step, or two, or three to get to the level of these guys," he admitted.
"I wasn't feeling good in the first week so I couldn't have ridden for GC (general classification) anyway.
"Also, it's not worth it for me to ride for 12th place in GC. If I can get some time and win a stage like this, it's worth so much more.
"I don't think I'm good enough to ride in the top 10 now but I hope to make a few steps in the future and hope to try in the future.
"But for now, definitely not."