ISTANBUL (AP) - Formula One champion Sebastian Vettel will again lead from the front at the Turkish Grand Prix after the German driver secured his fourth straight pole position of the season on Saturday.

The Red Bulls will start Sunday's race 1-2 on the grid after teammate Mark Webber posted the second quickest time, with Nico Rosberg carrying over his impressive form in practice to take third spot for Mercedes.

The 23-year-old Vettel showed that he has fully recovered from the crash that hampered his opening, rain-hit practice on Friday, and is in a perfect position to aim for a third Grand Prix win of the season.

"Straight away I felt comfortable in the car, felt the rhythm of the track very quickly," said Vettel, who clocked 1 minute, 25.049 seconds.

Webber's best lap was 1:25.454, while Rosberg managed 1:25.574.

McLaren driver Lewis Hamilton, who caught up and beat Vettel at the Chinese Grand Prix, will start from fourth place, while two-time former champion Fernando Alonso tries to get Ferrari its first podium of the season from fifth spot.

It was also the 23-year-old Vettel's fifth successive pole overall, as he led from the front to win the season-ending Abu Dhabi race and clinch the F1 title in November.

Neither Vettel or Webber went out for a final run, sparing their tires for the race.

"It is a strange feeling because the others are on track and there is nothing you can do," Vettel said. "It's important to handle your tire situation."

Webber, however, felt he could have been a little faster.

"I would have liked to have been a bit closer but these cars are very complex," the Australian driver said.

"In the end I'm happy with what I did. I would like to have had a couple more tenths to have the margin."

Vettel, who was patted on the back by Red Bull mechanics as he rejoined the paddock, looked thrilled at recovering his form. He sat out all of Friday's second practice and had completed only four practice laps in the first.

Although his crash had been more spectacular than anything else - debris spraying everywhere but Vettel unharmed - he was relieved at how smoothly things went in qualifying.

"I am happy and very pleased after a very bad shunt yesterday, and all the workload I managed to give to the mechanics yesterday," Vettel said.

"Apologies to the team and mechanics. I damaged the car pretty much yesterday so we missed a session in the afternoon, but they fixed it for today, and we did a very good job."

Last year's race in Turkey sparked a feud between Vettel and Webber that lasted most of the season.

Red Bull lost out on a 1-2 sweep when their wheels touched as Vettel passed Webber on the inside, forcing Vettel to spin out of the race. That handed Hamilton and his McLaren teammate Jenson Button a 1-2 finish.

"It was a different atmosphere for sure, it was a different race," Webber said. "We don't know how the race will evolve (on Sunday), at certain times we may be close to each other."

They may have Rosberg to contend with as well.

The German driver has hardly made a mistake so far in Istanbul, finishing second fastest in the first two practices, and fourth-quickest in the third session on Saturday morning.

"It's really great to see the progress we are making, strategy-wise we are very strong," he said. "I'm confident we can have a really good race."

Vettel had set himself up nicely for qualifying with the fastest time in the third practice, in which he was just 0.001 ahead of seven-time champion Michael Schumacher's Mercedes, and in which Webber was third quickest.

But the brief excitement at Schumacher's returning to the front of the grid was quickly dispelled when the 42-year-old placed only eighth in qualifying.

"Understandably, I am not happy at all with today's qualifying," Schumacher said. "It was just strange - it seemed that the more I pushed on my last lap, the more went wrong.

"I was at the limit of what I had in my hand, but the car was just sliding around and therefore I never got into my rhythm. It's a real shame after this morning's promising session."

Drivers had profited from the good practice weather to test their KERS power-boost systems and moveable rear wings, which are designed to help overtaking.

LAS VEGAS: Manny Pacquiao's trainer Freddie Roach would dearly love his fighter to put the gloss on his WBO welterweight title defence by knocking out Shane Mosley – if only to give a timely nudge to Floyd Mayweather.       

American Mosley, 46-6-1 with 39 knockouts, has yet to be stopped during his professional career.

And Roach has set his sights on Filipino southpaw Pacquiao becoming the first boxer to achieve the feat.

"We don't go into fights looking for knockouts but if the opportunity does come, I want that to happen," Roach said during the build-up to today's showdown at the MGM Grand Garden Arena.       

"Nobody else in the world has ever done that and when you do something no one else can, it just proves again how good you are and how dominant you are in the sport.       

"That is what Manny Pacquiao is and I want to prove to Mayweather we can do something he hasn't."

A year ago, Mayweather resisted a furious early onslaught by Mosley to preserve his unbeaten professional record with an unanimous points victory in a welterweight bout in Las Vegas.       

Mayweather has not fought since and boxing fans have long savoured the prospect of a showdown between the defence-minded American and the aggressive Pacquiao to decide the mythical title of the world's best pound-for-pound fighter.       

"That is why I want to knock this guy (Mosley) out just to give him (Mayweather) another dig and maybe give him some incentive to sign that contract," Roach said.

"He talks the talk but he won't sign and he won't get in the ring with us.

"I am tired of listening to this guy saying how he is the best fighter of all time and so forth and how much better he is than everybody else in the ring.

"If he wants to show it, then he has to prove it."

Mayweather had been expected to meet Pacquiao last year until negotiations collapsed over the American's demand for random drug testing.       

Mosley then stepped in to take the Filipino's place but he was outclassed by Mayweather in a non-title welterweight bout in May.       That left Mayweather with an unblemished career record of 41-0 with 25 knockouts.

The likelihood of the two fighters getting into the ring any time soon has further receded with Mayweather facing a September trial in Las Vegas on a misdemeanour battery charge.       

Pacquiao deferred any talk of a Mayweather mega-bout to his promoter after improving his own career record to 52-3-2 with 38 knockouts after a unanimous points victory over Mexican Antonio Margarito in November.       

"I'm not going to fight anybody as long as there is a problem with the decision of the promoter," the eight-time world champion said. "That's my promoter's job. I'm just a fighter to do my job and train hard for the fight."       

For Roach, a Pacquiao-Mayweather fight needs to take place simply for the good of the sport and all its fans.       

"Mayweather's the biggest challenger in the world for us and he's the hardest style for us to fight," Roach said. "I look forward to getting a game plan going." – Reuters       

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