Miguel Angel López (Astana Pro Team) had a straightforward first day as Volta a Catalunya leader on Friday's stage 5, but the Colombian warned that the final stage through Montjuic park on Sunday "could be a very different story."
Sunday's final stage features multiple ascents of the hilly Montjuic circuit in central Barcelona, and with rain forecast for the urban circuit, crashes are more than likely, as well as the usual run of attacks.
"I'm expecting a really big battle on that last stage, it'll be the key to it all," López told reporters after finishing tenth on stage 5 and closely shadowed by GC runner-up Adam Yates (Mitchelton-Scott).
His current advantage of 14 seconds over Adam Yates should be enough for stage 6, a hilly but relatively uncomplicated day - unless there are coastal cross-winds - through western Catalonia on Saturday, Lopez argued.
"For sure there will be a breakaway or a bunch sprint, I don't think it'll be too tough. But Sunday will be different," López commented.
Friday's run out of the Pyrenees down towards Barcelona was fast but straightforward, López said, "because we were watching the GC guys and hoped that a big break, with maybe eight or 10 guys should go clear. But that didn't happen, there were fewer at the end.
"However, I felt good despite the speed" - averaging 42.6 kph despite the first category climb of La Collada de Toses at the start - "and there weren't any problems.
"This isn't like the Giro d'Italia, where I hope to start the race in full condition, here I've been getting better little by little. And I hope that'll continue all the way to Barcelona."