Remco Evenepoel claimed his third win of this year's Vuelta a Espana on stage 18 as Jumbo-Visma's Sepp Kuss moved closer to winning his first Grand Tour.
Belgian Evenepoel, the 2022 winner, launched a solo attack from a breakaway group to win by almost five minutes.
But the Soudal Quick-Step rider, 23, has been out of contention since stage 13 and is now 13th overall.
He is almost 28 minutes off American leader Kuss, who came through the last big day in the mountains unscathed.
The 28-year-old increased his lead over second-placed Jonas Vingegaard from eight seconds to 17 with three stages remaining, with their Jumbo-Visma team-mate Primoz Roglic third.
But they are now acting as 'super domestiques' to Kuss, with the Dutch team set to become the first to win all three Grand Tours in the same year. Roglic won the Giro d'Italia in May and Vingegaard retained his Tour de France title in July.
"It's sure nice to be able to pay Sepp back," said Denmark's Vingegaard. "He has done so much for me and Primoz. Saturday is a tough long stage though so we have to be careful."
Kuss was shepherded through the dramatic Asturian landscape by his more illustrious team-mates before Friday's flat stage, which is followed by a demanding penultimate stage on Saturday.
Evenepoel will not be challenging on the final weekend but secured the king of the mountains title on the 179km ride from Pola de Allande on Thursday.
He attacked on the first of two climbs of the Puerto de La Cruz de Linares late in the stage to claim the 50th professional win of his career.
Stage 18 results
1. Remco Evenepoel (Bel/Soudal Quick-step) 4hrs 47mins 37secs
2. Damiano Caruso (Ita/Bahrain Victorious) +4mins 44secs
3. Andreas Kron (Den/Lotto Dstny) +5 mins 10secs
4. Max Poole (GB/DSM-Firmenich) +5mins 12secs
5. Paul Ourselin (Fra/Totalenergies) +5mins 17secs
6. Julien Bernard (Fra/Lidl-trek) +6mins 11secs
7. Egan Bernal (Col/Ineos Grenadiers) +7mins 01secs
8. Juan Ayuso (Spa/UAE Team Emirates) +9mins 29secs
9. Enric Mas (Spa/Movistar) Same time
10. Sepp Kuss (US/Jumbo-Visma)
General classification after stage 18
1. Sepp Kuss (US/Jumbo-Visma) 65hrs 31mins 27secs
2. Jonas Vingegaard (Den/Jumbo-Visma) +17secs
3. Primoz Roglic (Slo/Jumbo-Visma) +1min 8secs
4. Juan Ayuso (Spa/UAE Team Emirates) +4mins
5. Mikel Landa (Spa/Bahrain Victorious) +4mins 19secs
6. Enric Mas (Spa/Movistar) +4mins 30secs
7. Cian Uijtdebroeks (Bel/Bora-hansgrohe) +7mins 37secs
8. Aleksandr Vlasov (Rus/Bora-hansgrohe) +8mins 35secs
9. Joao Almeida (Por/UAE Team Emirates) +10mins 20secs
10. Santiago Buitrago (Col/Bahrain Victorious) +12mins 20secs