On Monday's rest-day, team management was keen to play down any notion that having two riders in contention for the overall title could be a potential source of controversy, but the Cantabria time trial was always going to see the leadership debate back in the headlines in the following morning's newspapers.
As was widely expected, Valverde, who started the day second overall behind Simon Yates (Mitchelton-Scott) and seven seconds ahead of Quintana in third, performed better than his teammate on the rolling 32km course between Santillana del Mar and Torrelavega.
Though perhaps not as much as predicted, the 35 seconds that separated the pair on the stage means that Valverde is now 42 seconds ahead of Quintana, who slipped off the podium at the hands of Steven Kruijswijk (LottoNL-Jumbo).
"In reality, I'm closer to first place – you have to acknowledge that – but that doesn't mean that I'm the sole leader," Valverde said.
"We also have Nairo, who's going well. It's clear that I did better in the time trial, but we'll see how it is in the mountains that are coming up."
Valverde may be closer to first place than Quintana, but he's further away from it than he was at the start of the day. One of the big question marks at the start of the day was who would end the day in the red jersey – with many seeing it as a case of how much time Valverde would recoup – but in the end, Yates sprang a surprise in going seven seconds quicker.
Valverde, who is now 33 seconds off the lead, said he struggled with the headwind in the second part of the course but was happy with his ride and could only tip his cap to Yates.
"I felt good. I went out very hard and attacked the first past of the course. On the middle part I didn't manage to find a great rhythm but in the final part I got back on it and finished well. But the way I see it, I did a good time trial," he said.
"It's clear it's a step back of seven seconds, but it's also true that we're still in the fight, it's still a matter of seconds, and of course we're not going to roll over."
Indeed, the top three are all within a minute of each other, while sixth-placed Miguel Angel Lopez (Astana) is only at 1:34. With three big mountain stages and summit finishes to come – Wednesday's finish at the Balcón de Bizkaiai is followed at the weekend by a double-header in Andorra – it's still all to play for.
"It's still close, and that adds to the emotion of the Vuelta," said Valverde, who refused to indulge any conjecture that Yates might crack in the final days as he did at the Giro d'Italia earlier this year.
"The Giro is the Giro, the Tour is the Tour, and the Vuelta is the Vuelta," he said. "Anything can happen."