Tasmanian Richie Porte has reinforced the view he's a future Tour de France title contender by cooly closing down multiple attacks launched against race leader and team-mate Chris Froome.
Richie's an absolute gem of a person and I'm really lucky to have him riding with me.
Yellow jersey holder Froome was quick to praise his Sky team-mate at the end of Tuesday's eventful 16th stage to the south-eastern town of Gap won by escapee Rui Costa of Movistar.
Porte was forced to reel in repeated attacks by Saxo-Tinkoff's Alberto Contador - one of Froome's main rivals - on the final climb of the day.
The Australian was briefly distanced by a late surge from Contador's lieutenant Roman Kreuziger but managed to claw his way back to the yellow jersey group and help Froome on the dangerous descent.
Stellar job from my roomie @richie_porte in a sketchy & explosive final, thanks mate!— Chris Froome (@chrisfroome) July 16, 2013
"I was lucky to have Richie Porte there for me," Froome said after the 168km stage that started in the Provence village of Vaison-la-Romaine.
"I don't know how many times he covered their attacks but it must have been close to about 10 times.
"He's an absolute gem of a person and I'm really lucky to have him riding with me."
Porte said Sky had expected Saxo-Tinkoff to attack on the climb and the descent off the Col de Manse.
"It's nice to be able to cover those moves for Chris and make it a little bit easier on him," the 28-year-old said.
"(But) hats off to them (Saxo-Tinkoff) ... they were good today.
"The Tour is not over yet if they are going to ride so aggressively."
Think I grew a few grey hairs after today's finale #stress— Richie Porte (@richie_porte) July 16, 2013
Porte on Sunday dropped the best climbers in the world before launching Froome to a famous victory on Mont Ventoux.
The Tasmanian will treat Wednesday's 32km time trial as "a rostered day off" before he's called on to assist Froome in the final three Alpine stages.
Former winner Cadel Evans (BMC) again struggled on Wednesday slipping to 17th overall some 16min 40sec down.
Michael Rogers (Saxo-Tinkoff) is the best placed Australian in 12th just under 11 minutes behind Froome.
Orica-GreenEdge rider Cameron Meyer and Adam Hansen (Lotto-Belisol) flew the Aussie flag in the day's breakaway but couldn't match Costa on the final climb.
SBS will broadcast all stages of the Tour de France live.