Tasmanian Porte capitalized on a remarkable display of control from his teammates on what many consider the toughest stage of this year's race before chipping clear heading into the final kilometre to win by four seconds.

Henao was third into Beasain, narrowly edged out by Samuel Sanchez (Euskaltel-Euskadi) to retain the yellow jersey. The pair led home a group of seven riders, all finishing four seconds behind Porte. The group also featured Nairo Quintana (Movistar), Pieter Weening (GreenEdge), John Gadret (AG2R), Alberto Contador (Saxo-Tinkoff), and Katusha's Simon Spilak.

Spearheaded for the entire day by Team Sky, an already tough stage featuring no less than ten categorized climbs was made worse by torrential rain, sleet and even snow as the Basque Country again lived up to its reputation.

"It was the last road stage and everybody wanted to be in the breakaway. In the end the guys up the road were the guys who had the legs to be there. They were strong riders but [Vasil] Kiryienka and Xabi [Zandio] were just absolutely incredible. They controlled things all day," stage winner Porte told RoadCycling.com.

"[The weather] was the same yesterday and I think tomorrow could be much the same. At the end of the day everybody’s in the same boat. Everybody just got on with it. I think there was no better place to be today than riding up at the front. The team were just incredible. We came here with a depleted team and I think everyone has stepped up and done a brilliant job," Porte added.

Porte remains third overall, now level on time with Quintana six seconds back on Henao, who remained glued to the wheel of Sanchez in defence of yellow.

This year's Vuelta Ciclista al Pais Vasco will be decided on Saturday in a 24 kilometre individual time trial in Beasain. Porte is expected to take the overall race victory by delivering a dominant performance in tomorrow's time trial.

"Tomorrow is going to be a whole different ball game. It’s not a typical time trial. There’s some climbs in there and I’ll take it as it comes," Porte commented.

Stage winner Richie Porte and race leader Sergio Henao are using the premium version of the RoadCycling.com training tracker software to track and plan their training. Want the same advantage as Porte and Henao? Sign up for the premium version here. You'll also have easy login access to your training data from all pages here on RoadCycling.com.

For our USA-based readers we have 2013 Vuelta Ciclista al Pais Vasco video highlights from all stages this week in our videos section .

Gear up for the new cycling season in Roadcycling.com's road bike shop and follow Roadcycling.com on Twitter, Facebook and Google+.