Julian Alaphilippe will put his hopes of winning the Tour of California on hold in an effort to help British team-mate Mark Cavendish win a fourth stage.
The Frenchman won stage seven's summit finish on Mount Baldy to take a two-second lead over Slovak Peter Sagan.
However, with Sunday's finale expected to end in a bunch sprint, Alaphilippe, 22, said: "We have to go with our original plan to try and win with Mark.
"Then we defend the yellow jersey. If not, it won't be the end of the world."
Etixx - Quick-Step rider Alaphilippe rode away from the field on the ascent on Saturday to win in a time of three hours, 42 minutes, 13 seconds - 23 seconds ahead of Team Sky's pre-race favourite Sergio Henao.
Overnight leader Sagan, who is not renowned for his climbing ability in the high mountains, produced a gutsy ride to finish sixth on the stage, 47 seconds behind Alaphilippe, and retain his hopes of winning the overall title.
There are bonus seconds available at the finish line and in a mid-stage sprint and Alaphilippe said: "It is clear Sagan is faster than me."
Sagan has already secured three second places in sprint finishes in this year's race, to add to his victories on stage four and in the time trial.
The eight-day race ends on Sunday with a 105km road stage from Los Angeles to Pasadena.
Stage six result:
1. Julian Alaphilippe (Fra/Etixx - Quick-Step) 3hrs 42mins 13secs
2. Sergio Luis Henao Montoya (Col/Team Sky) +23secs
3. Ian Boswell (Col/Team Sky) +23secs
4. Joseph Lloyd Dombrowski (US/BMC Racing Team) +36secs
5. Ricardo Zoidl (Aut/Trek Factory Racing) +45secs
Overall standings after stage six:
1. Julian Alaphilippe (Fra/Etixx - Quick-Step) 25hrs 58mins 25secs
2. Peter Sagan (Svk/Tinkoff-Saxo) +2secs
3. Sergio Luis Henao Montoya (Col/Team Sky) +33secs
4. Joseph Lloyd Dombrowski (US/BMC Racing Team) +1min 10secs
5. Robert Gesink (Ita/Tinkoff-Saxo) +1min 11secs
9. Peter Kennaugh (GB/Team Sky) +1min 40secs
13. Tao Geoghegan Hart (GB/Axeon Cycling Team) +2min 32secs