Simon Yates extended his general classification lead by seven seconds, but it was Rohan Dennis who bowed out of the Vuelta a Espana with a commanding individual time trial display on stage 16.
Mitchelton-Scott rider Yates talked up the time trial abilities of his closest GC rival Alejandro Valverde during the rest day on Monday, but he managed to improve his grip on the red jersey on the flat 32-kilometre route from Santillana del Mar to Torrelavega
The Briton's time of 39 minutes, 25 seconds was enough for 13th and means he now leads Valverde by 33 seconds in the overall standings.
But neither came close to catching Dennis, who beat BMC Racing team-mate Joey Rosskopf and Team Sky's Jonathan Castroviejo by 50 seconds by crossing the line in 37 minutes, 57 seconds.
While Yates and Valverde remain the GC's leading duo, Nairo Quintana lost 42 seconds and slipped to fourth following a strong display from Steven Kruijswijk.
Kruijswijk looked like a challenger for the stage win when he reached the first checkpoint five seconds quicker than Dennis, but he was unable to maintain his speed and had to settle for fourth.
However, the Dutchman still gained 37 seconds on Yates and now sits in a podium position and just 52 adrift of top spot.
DOMINANT DENNIS IS DONE
It was another stunning ITT performance from Dennis, who added to his win in the opening stage in Malaga for his sixth victory in the format this season.
Those added to his triumph on stage 16 of this year's Giro d'Italia makes him just the fourth rider this century to win three Grand Tour ITTs in a single season.
It will be Dennis' last act of the Vuelta, though, as he confirmed he will abandon the race to prepare for the UCI Road World Championships in Innsbruck.
"I'm heading home now and just preparing for the time trial and team time trial at worlds," he said.
"I tried to control it at the start and finish and make my move in the middle section and it worked out perfectly. I knew I was on a good one just looking at my power on the Garmin, but really I didn't know what [Michal] Kwiatkowski and a couple of the later guys could do.
"All I knew was what Castroviejo was doing at the time and he's a good indicator of if you're doing well or not."
1. Rohan Dennis (BMC Racing) 37:57
2. Joey Rosskopf (BMC Racing) +0:50s
3. Jonathan Castroviejo (Team Sky) +0:50s
4. Steven Kruijswijk (LottoNL-Jumbo) +0:51s
5. Michal Kwiatkowski (Team Sky) +0:51s
1. Simon Yates (Mitchelton-Scott) 64:52:58
2. Alejandro Valverde (Movistar) +0:33s
3. Steven Kruijswijk (LottoNL-Jumbo) +0:52s
1. Alejandro Valverde (Movistar) 116 points
2. Peter Sagan (Bora-Hansgrohe) 83 points
3. Dylan Teuns (BMC Racing) 73 points
King of the Mountains
1. Luis Angel Mate (Cofidis) 64 points
2. Thomas De Gendt (Lotto-Soudal) 57 points
3. Benjamin King (Team Dimension Data) 56 points
The riders face a daunting 157km ride from Getxo to Balcon de Bizkaia that includes 3,000m of climbing and a difficult finish up Mount Oiz with gradients reaching 18 per cent.