Los Angeles - Former Tour de France winner Bradley Wiggins retained the Tour of California overall lead on Friday as Colombia's Esteban Chaves won the sixth stage from Santa Clarita to Mountain High.
Wiggins, who took the lead with a triumph in the second stage individual time trial on Monday, finished fifth in the toughest stage of the race and extended his overall lead to 30 seconds going into the final two stages this weekend.
Orica rider Chavez powered solo to win the 152km stage that ended in the San Gabriel Mountains northeast of Los Angeles in a time of 4 hours 9 minutes 13 seconds.
On a day when temperatures again soared into the upper 30 degrees Celsius, the Colombian climber attacked from a small group in the last 5km of the final ascent, putting some room between himself and David de la Cruz of Spain and American Tom Danielson.
De la Cruz finished second, 13 seconds back, and Danielson was third, 41 seconds adrift.
Briton Adam Yates was fourth, 53 seconds back, with Wiggins fifth in the same time.
"Surprisingly, I was pretty comfortable with four kilometres to go," Wiggins said. "Then the altitude kicked in."
He had enough left, however, to hold off his nearest rival in the overall classification, Australian Rohan Dennis.
Garmin's Dennis finished seventh, 55 seconds off the lead to surrender two seconds to Wiggins overall.
"We had Tommy D off the front, so we were watching what Sky was doing," Dennis said.
"Hopefully, they were riding hard and they would just blow up like they did on Diablo. But it wasn't quite as steady an uphill, there was some downhill to recover. When we got to the last kilometre I don't think I've pedaled like that for awhile."
The race continues on Saturday with a 143km stage from Santa Clarita to Pasadena that features two significant climbs, with the final stretch all downhill.
The tour concludes on Sunday in Thousand Oaks, in rolling countryside west of Los Angeles.
Results on Friday in the sixth stage of the Tour of California, 152km from Santa Clarita to Mountain High:
1. Esteban Chaves (COL/Orica) 4 hr 09min 13sec
2. David de la Cruz
(ESP) at 13sec
3. Tom Danielson (USA) at 41
4. Adam Yates (GBR) at 53
5. Bradley Wiggins (GBR) same time
Also: 7. Rohan Dennis (AUS) at 55.
Overall standings after six of eight stages:
Bradley Wiggins (GBR/Sky) 22:03:42
2. Rohan Dennis (AUS) at 30sec
Lawson Craddock (USA) at 1:48
4. Tiago Machado (POR) at 2:02
Yates (GBR) at 2:14