Jason Kenny warmed up for the defence of his Olympic sprint title by regaining the world title in the same discipline to capture Great Britain's third gold medal at the UCI Track Cycling World Championships. Kenny came from behind after losing the opening ride to beat Australian Matthew Glaetzer 2-1 in a stunning performance in London - the scene of his double Olympic gold in 2012.

But despite Britain claiming a third world title - their first in an Olympic discipline at the championships - it was a night of contrasting fortunes for the host nation as Mark Cavendish saw his hopes of competing for a first medal at the Games in Rio all but ended after finishing off the podium in the men's omnium. The former road race world champion finished sixth overall despite a spirited showing in the final points race event.

However, little could detract from Kenny's achievement, which saw him make a timely return to form just five months out from his attempt to retain his Olympic title. "The last few rides were tough and very close together," the 27-year-old said. "We were both knackered and there was a bit of luck as Matt had to lead it out. He's the only person in the arena whose legs feel worse than mine.

"The time was slow and it wasn't the prettiest race of them all. We tweaked with something on the bike and found some time. To qualify second I was really pleased with that and it just transferred into the race.

"Last year was disappointing and I've made a promise to make the most of every single day. I was disappointed in the team sprint and I didn't feel like myself and I felt responsible for that. we have the tools it is jus putting it together."

Cavendish saw his dream of winning an Olympic medal collapse after finishing outside of the medals in the men's omnium. The Isle of Man rider entered the final round of the six-discipline event, the points race, in fifth position but despite winning three of the 16 sprints was unable to force his way onto the podium and ended up down in sixth.

The result, which saw Fernando Gaviria dramatically retain his title ahead of Germany's Roger Kluge and Glenn O'Shea of Australia after the trio all finished level on 191 points, means Cavendish is likely to finish his career without Olympic success. There are only five places on the men's endurance team this summer and the 30-year-old, who will pair up with Sir Bradley Wiggins in the madison in the final event of the championships, was set a target of winning at least a bronze medal in order to be in contention for a spot.

British Cycling technical director Shane Sutton said: "The name doesn't help him 'the greatest road sprinter of all time'. He's shown some real quality there and we'll sit down with Mark and discuss where we go from here.

"[Rio] is something we will discuss with him. We'll have a look at the analysis from this week and see where he is at. That fifth rider is going to be part of that team pursuit, which is a big medal opportunity

"At the moment emotions are high, he road some great sprints out there but at the end of the day didn't get the result he wanted. We're not discounting Mark at this moment in time. That decision is between him, us and the coaching team so we'll sit down and see where we go."

Emily Nelson marked her world championships debut with a credible fifth place finish in the women's points race, eventually won by Katarzyna Pawlowska of Poland. The Newport-born rider led at the half-way point after winning the fifth sprint but was eventually overtaken in a high class field.

"It has been incredible," said the 19-year-old, who is already a World Cup silver and bronze medallist. "The crowd have been amazing. Every time I went for something they got behind me and it really, really helps and it just gives you that extra push. Obviously I am gutted that I did not medal but I am so happy with fifth. I am happy with how I road. There are some really good riders in there and I was up there with them. I am still finding my feet and this will give me massive confidence."

Meanwhile, Laura Trott will go into the final day of competition in contention to claim a second gold medal in the women's omnium. Already a gold medallist in the scratch race, Trott is second in the 20-woman field, behind rival Sarah Hammer on count-back with both riders on 112 points after finishing second behind the American in the elimination race - the third of six events in the competition.