KATHERINE GRAINGER'S Grainger's quest to become Britain's most successful female Olympian at Rio 2016 endured choppy water on day one of competition.

The 40-year-old from Maidenhead, along with rowing partner Vicky Thornley, let slip a lead with 500 metres to go to finish second in their heat of the double sculls at the Lagoa Rodrigo de Freitas in the heart of Rio.

However, with the first three going through to the next rouond, Grainger remains on target for a fifth Olympic medal - having won gold in London and silver in 2008, 2004 and 2000.

Sir Steve Redgrave said the pair would not be happy with that performance. The rowing icon, who won five gold medals and five separate Olympics, said: "They had to make a statement today because they haven't been able to make a statement for the last two years.

"We know they have got pedigree, and this is the first time we have really seen then fight.

"It is a positive because they have moved forward from what they have been doing, but they won't be happy. At least they are in the frame."

Grainger and Thornley got off to a cracking start in the choppy waters and held a 0.61 second lead with 500 metres to go. But Grainger, who won gold with Anna Watkins in London four years ago, and partner Thornley in the bow seat found themselves passed by Lithuania and pushed all the way to the finish line by the French.

"Second place is second place," said Olympic rowing medallist, James Cracknell. "If you had said at half way they would come second, you would have been disappointed. 

"The girls have got boat speed, but they have not got the endurance."

The semi-finals of the women's double sculls take place on Tuesday at 2.10pm BST.