Hayden celebrates claiming pole at Estoril

The reigning world champion lapped the 4.18km (2.6-mile) Estoril circuit in one min 36.301 secs on his Honda.

Stoner was second fastest in 1:36.341, with five-time champion Valentino Rossi (1:36.576) taking third on the grid.

Australia's Stoner, who leads the standings with 271 points after eight wins, can clinch the championship with a victory in Portugal.

Rossi trails Stoner by 85 points and needs a victory to keep his title hopes alive.

I want to lead into the first turn on Sunday and have some fun Nicky Hayden

But Stoner said: "It's going to be a very, very difficult race. We've got a lot of competition and there's a lot of riders doing some very consistent lap times.

"We've got another good grid position so maybe we can have another good result on Sunday."

Hayden, winless so far this season, said: "This pole is a big thank you to the team who have stuck with me and worked so hard during the dark times.

"In the last section I knew I just had to pull out the pin and go for it because I had nothing to lose.

"It was so good to return to pit lane and see everybody smiling again. I want to lead into the first turn on Sunday and have some fun."

Rossi was not too disappointed with his display, saying: "Of course pole is always the target but the most important thing is to be on the front row.

"The new Michelin race tyres are working well here and the other Michelin riders are fast too so we can hopefully all be close to Stoner."