Defending champion Vincenzo Nibali accused Giro d’Italia leader Tom Dumoulin of being “a little bit too cocky”, with three stages remaining.
Dumoulin was ninth on stage 18 and retained a 31-second lead over Nairo Quintana, with Nibali third overall.
Dutchman Dumoulin said his two closest rivals were “clearly working together” and hoped they would lose places.
Nibali countered: “Has he ever heard of karma? He should do less talking because even he might miss the podium.”
American Tejay van Garderen won Thursday’s 18th stage, edging out Mikel Landa at the finish in Ortisei.
It was a first individual Grand Tour stage victory for the 28-year-old, who helped his BMC team to win team time trials at both the Tour de France and Vuelta a Espana in 2015.
Dumoulin finished ninth, more than one minute behind Van Garderen, but held off attacks by Quintana to maintain his overall advantage on the Colombian.
Britain’s Adam Yates finished 12th and moved up to ninth overall.
Dumoulin, seeking to become the first Dutch winner of the event, crossed the line in the same time as Quintana at the end of the 137km stage from Moena to Ortisei.
Defending champion Nibali remains one minute 12 seconds behind, while Thibaut Pinot of France gained more than a minute on the leading trio in the general classification.
Asked about Nibali’s comments, Dumoulin said: “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.”
Friday’s 19th stage is a 191 km ride from San Candido to Piancavallo featuring four climbs and Dumoulin insisted Quintana, the 2014 champion and two-time Tour de France runner-up, is still “the strongest climber” in the race.
The 100th Giro ends in Milan on Sunday.
Stage 18 result
1. Tejay van Garderen (US/BMC Racing) 3hrs 54mins 03secs
2. Mikel Landa (Sp/Team Sky) Same time
3. Thibaut Pinot (Fr/FDJ) +8secs
4. Domenico Pozzovivo (It/AG2R) Same time
5. Jan Hirt (Cze/CCC) +11secs
6. Ilnur Zakarin (Rus/Katusha) +24secs
7. Bauke Mollema (Ned/Trek)+34secs
8. Steven Kruijswijk (Ned/LottoNL) Same time
9. Tom Dumoulin (Ned/Sunweb) +1min 6secs
10. Nairo Quintana (Col/Movistar) Same time
Overall classification after stage 18
1. Tom Dumoulin (Ned/Sunweb) 80hrs 00mins 48secs
2. Nairo Quintana (Col/Movistar) +31secs
3. Vincenzo Nibali (It/Bahrain) +1min 12secs
4. Thibaut Pinot (Fr/FDJ) +1min 36secs
5. Ilnur Zakarin (Rus/Katusha) +1min 58secs
6. Filippo Pozzato (It/Wilier Triestina) +2mins 07secs
7. Bauke Mollema (Ned/Trek) +3mins 17secs
8. Steven Kruijswijk (Ned/LottoNL) +5mins 48secs
9. Adam Yates (GB/Orica) +7mins 06secs
10. Bob Jungels (Lux/Quick-Step)+7mins 24secs