For the second day running, Alberto Contador (Trek-Segafredo) turned in an impressive display of climbing power on the Ruta del Sol, netting the overall lead on the race's sole summit finish of Mancha Real.
The stage win though, did not prove possible for the Spanish veteran, and with only a handful of seconds between the top names by the finishing line, winning outright now hinges on Friday's short, punchy time trial.
Contador and Trek-Segafredo once again played a very aggressive game, working hard with Team Sky to pull back daylong breakaway Tim Wellens (Lotto-Soudal). After Warren Barguil (Sunweb) had briefly gone clear at the foot of the climb, Contador then benefited from a massive drive by team-mate and Trofeo Laguiglea winner Fabio Felline (Trek-Segafredo) before punching hard on the accelerator himself.
Contador's single attack, at three kilometres from the line, was so successful it scattered the entire field and left him at the head of the race and with an initial margin of over 10 seconds. But then as the slopes eased slightly, the riders behind could recoup their losses a little and eventual stage winner Thibaut Pinot (FDJ), followed by the rest, began to reel him in.
"It was a very hard ascent, and we wanted to drive as hard as we could in the team," Contador said afterwards. "I maybe went for it too early, there was a strong headwind, but I wanted to be sure my attack counted.
"My pulse rate went up quite high quite soon, but that's what always happens to me in these early races. It would be the same in the Algarve when I've raced there. The climb, finally, was just a little too long for me, although I was surprised that Pinot caught me. I'm disappointed I didn't win, because I wanted to do that to thank the team. But overall I'm pleased.
"Not knowing the climb didn't help. I think maybe if I'd got to the last 200 metres alone I would have won, but that's all there is. In any case, given I'm building towards Paris-Nice, this was a very good sign for the future."
Contador pointed out that with so many riders so close together, it would be no easy matter to hold onto the overall lead. Seven riders remain within 26 seconds of the leader prior to tomorrow's decisive time trial, and with such small time gaps, any of them in theory, could emerge the winner.
Wout Poels (Team Sky), sixth at 11 seconds, showed in last year's early season how strong he can be against the clock, Pinot is a defending national time trial champion, and so too, is Ion Izagirre (Bahrain-Merida) for Spain, in fourth place at five seconds overall.
"It's going to be very complicated," Contador observed, "Izagirre is a really good time triallist, and the course suits him, too."
Contador has yet to see tomorrow's 12 kilometre course in Cordoba, but differences will, in any case, likely be minimal. In last year's much longer time trial in the Ruta del Sol, only 46 seconds separated the top 20 on the 21 kilometre stage, won by Tejay Van Garderen (BMC Racing). The 2017 Ruta del Sol, then, looks certain to go down to the wire.