Rio Olympics 2016: Katherine Grainger and Victoria Thornley make final

Britain's Katherine Grainger qualified for her fifth Olympic final as she and Victoria Thornley came second in their double sculls semi-final in Rio.

Grainger, 40, won silver at three successive Games before finally claiming gold at London 2012 - and then taking a two-year sabbatical.

Jonny Walton and John Collins in the double sculls, and pair Alan Sinclair and Stewart Innes also made finals.

But Britain's lightweight men's four failed to make it through the semis.

Katherine Copeland will not retain her Olympic title as she and Charlotte Taylor went out in the repechage of the lightweight double sculls.

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It leaves the British rowing team with six boats so far through to finals in Rio.

Earlier, Alan Campbell reached the semi-finals of the men's single sculls by finishing second in his heat.

The 33-year-old was the fifth fastest qualifier, 4.97 seconds outside the leading time, set by Croatia's European champion Damir Martin.

Campbell won bronze at London 2012, and is the first Northern Irishman to compete at four Olympic Games.

Walton and Collins finished third in their men's double sculls semi-final

Grainger & Thornley hit form

Since returning to rowing two years ago, Grainger had struggled to find the same kind of dominant form that helped her win gold alongside Anna Watkins in 2012.

However, Grainger and Thornley impressed in their semi-final in Rio, finishing just under two seconds behind Poland's Magdalena Fularczyk-Kozlowska and Natalia Madaj.

Their hopes were boosted further as the world champion pair from New Zealand and highly-fancied Australians both failed to qualify for the final.

"Getting a medal is always the most thrilling, exciting, wonderful thing you can do at an Olympics," said Grainger.

"Right now it is about getting the best performance out of the two of us and if that's fast enough that's where we want to be."

Thornley, 28, said: "We're in an Olympic final. It probably is our best performance as a pair. There's a lot of pressure in a semi-final.

"There's all to play for and we haven't shown everything yet. Today is a giant leap forward; we've put a lot of work in the last six weeks."

Analysis - James Cracknell, double Olympic champion

"That's a step up from anything Grainger and Thornley have shown over the last two years since Katherine came back.

"The best thing is not only have they qualified, they would have come second in the other semi, so they are right in the mix for a medal.

"The Poles might get them again, they have been the form crew of the season, but they are in the mix."

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