Pendleton claimed a 2-0 final win over Lithuania's Simona Krupeckaite to win the title for a sixth time after successes in 2005, 2007, 2008, 2009 and 2010.

"This is probably the most significant and probably the most emotional, being the last time I'm going to do this," said Pendleton, who intends to retire after August's Olympic track programme.

"It means a lot to me. It probably means as much as the first one (in Los Angeles), which was special, because I never thought I had the ability to be world champion."

The Briton won the first of the best-of-three final before Krupeckaite was disqualified for impeding in the second match - handing Pendleton victory.

"I'm delighted I won but it's nice to win by crossing the line first - relegations always make it a bit weird," she added.

"It's a shame in some respect and it's not great for the crowd either, but they're the rules."

It was her ninth world title in all, with one keirin - an event in which she is set to ride on Saturday - and two team sprint wins to her name.

The key to victory was a stunning come-from-behind semi-final triumph over defending champion Anna Meares of Australia - a duel which was full of drama and proved Pendleton's determination for glory at the London Olympics is far from diminished.

Pendleton lost control and crashed in the first bout - suffering track burn to her right shoulder, elbow and hip - before being granted a reprieve in the second as Meares was adjudged to have impeded her opponent by going outside the sprinters' lane.

The officials' decision set up a deciding contest, which Meares led out on the last of three laps, but Pendleton responded by accelerating around her rival and won in a photo-finish.

After four successive sprint wins, Beijing gold medallist Pendleton was third in Apeldoorn in 2011, but now she is on top of the world once more.

Meares, who demonstrated her supreme form by breaking the world record in qualifying, won the ride-off for bronze with a 2-0 success over Ukraine's Lyubov Shulika.

Rivalry

"We were both pushing ourselves to the limit," said Pendleton of her semi-final against Meares.

"With Anna's qualifying time being so exceptional yesterday I knew I had to race a lot better than I ever had before.

"It's given me a lot of confidence. I thought this was going to be a stepping stone and I was hopeful that I might do a better sprint performance than I did in London at the World Cup.

"I definitely feel I fulfilled that and got the bonus of a world title. I know I was crying, but honestly I am delighted."

The announcement of Pendleton's win - which came as she was preparing for a deciding match with Krupeckaite - was greeted by joy from the British team pen, but there were audible boos from the crowd, already upset as Meares had to settle for bronze.

"There was some pretty interesting media in the days leading up to competition, in terms of giving the Brits a bashing," noted Pendleton.

"We did feel like it was going to be a tough crowd and a tough environment to perform in.

"Everyone on the team has already exceeded expectations on what we aimed to achieve coming to the World Championships.

"There was talk early doors that we weren't even going to be here, we were just going to train through to the Olympics. We're glad we came."

Meares is hoping to gain her revenge later in the year at the London Olympics.

"It was very disappointing to feel that I had progressed to the final - and then to lose so agonisingly," she said.

"Unfortunately I gave her a second chance and she took full advantage.

"I feel more disappointed because I know I am capable of winning. I just couldn't convert it.

"It's tit for tat. I won in London (World Cup earlier this year); she won in Melbourne. If we're going on that pattern, it's my turn next."

British showdown

Four-time Olympic gold medal winner Sir Chris Hoy and Jason Kenny, the defending champion, advanced to Saturday's semi-finals in the corresponding men's event - where the room-mates are poised to meet each other.

Hoy claimed a 2-1 win over Robert Forstemann of Germany and Kenny beat France's Kevin Sireau by the same margin.

Just one of the duo can represent Britain at the London Olympics under the one rider or team per nation per event rule - but both are in the world's top four four months out from the Games.

Hoy's win in the decider with Forstemann was by a tiny margin and was only confirmed after a photo finish.

Kenny, meanwhile, proved his strong form by ousting the world record holder.

France's Gregory Bauge, the 2009 and 2010 world champion, who was stripped of last year's title for an anti-doping offence, is set to meet Australia's Shane Perkins in the second semi-final.

Bauge beat Germany's Stefan Boetticher 2-0, while Perkins advanced 2-1 at the expense of Mickael Bourgain, after the Frenchman was relegated in the deciding race.

Clancy denied

There was disappointment for Britain's Ed Clancy in the omnium after he narrowly missed out on a medal despite winning the final event, the kilo time-trial.

Australia's Glenn O'Shea took gold with an overall tally of 22 points, Canadian Zach Bell silver on 28 points, with Clancy losing the bronze to Lasse Norman Hansen.

Both men finished on 29 points but the Danish rider had a lower cumulative total in the timed events.

"To get close is good - it still bodes well for the Olympics," said Clancy.

Another of the British contingent, Laura Trott, is well placed after the first three events of the women's omnium.

The 19-year-old produced a tactical masterclass to win the points race and shoot up to equal first place alongside Australia's Annette Edmondson on 11 points. The final three events take place on Saturday.

Trott's team-mate Dani King took fourth in the scratch race, won by Poland's Katarzyna Pawlowska.