Ortisei - Two-time champion Vincenzo Nibali upped the Giro d'Italia victory stakes Thursday by warning rival Tom Dumoulin not to get "too cocky" as he looks to become the first Dutch pink jersey winner.
"He's shown he's strong while racing, but he shouldn't get carried away when he's talking," Nibali said after a thrilling day of racing on an 18th stage won by American Tejay Van Garderen (BMC).
"If you ask me, he's a little bit too cocky. Has he ever heard of karma? He should do less talking and keep his feet on the ground because even he might miss the podium."
On the third of five days in the high mountains Sunweb team leader Dumoulin dug deep amid a series of attacks to protect his lead of 31secs on Colombian Nairo Quintana (Movistar) and his 1min 12sec advantage on Bahrain team leader Nibali.
But a post-stage spat means that on Friday's 19th stage, the penultimate day of climbing on the 100th edition, fireworks could go off.
Angered by Nibali and Quintana, who both launched futile attacks on the Dutchman in a bid to loosen his grip, Dumoulin later poked fun at the pair when they failed to close down a late attack by Frenchman Thibaut Pinot.
Pinot came over the finish line in third place, just eight seconds behind Van Garderen to move to within 24secs of Nibali and threaten the Italian's hopes of a possible podium place in Milan on Sunday.
"Vincenzo and Nairo were clearly working together and they lost one minute on guys like Pinot and (Domenico) Pozzovivo," Dumoulin said immediately after the finish.
"I really hope that riding like this, they will lose their podium spot in Milan, that would be really nice, and I would be really happy."
But after being read Nibali's comments, Dumoulin sat back and replied: "And then he calls me cocky! Those are also very strong words from his side."
He added: "They're only trying to make me lose. Until today I had no problems with Nibali. Only today I didn't like his riding in the final."
A 191 km ride from San Candido to Piancavallo on Friday features four climbs including a final, 15.4 km ascension featuring steep gradients of up to 14per cent.
"I don't know the climb, only from the book, but it's another hard day," said Dumoulin, who insisted Quintana, the 2014 champion and two-time Tour de France runner-up is still "the strongest climber" on the race.
"It's a difficult final climb," warned a disappointed Quintana, who admitted Movistar's tactics had fallen short.
"We stuck to our gameplan but every time I tried to attack Dumoulin countered. I'm disappointed."
But after Thursday's comments, Dumoulin's history-making bid could be about to get harder.
Nibali added: "Until now, he's been the strongest. Today he was even a little lucky. But winning the Giro is very difficult.
"He's been impeccable up till now, but it's not over yet."