Windsurfer Bryony Shaw, who was brought up in Oxford, says she is still on course to claim back-to-back Olympic medals despite seeing the start of her campaign hampered by a dip in the sea in Tuesday’s heats.

Shaw, who claimed bronze in Beijing four years ago, looked to have made a flying start to her mission in Weymouth after surging into third in the opening race – only to scramble home seventh after capsizing.

The second and final race of the day brought further frustration, with the 29-year-old forced to fight her way through the pack from eighth to sixth.

There are a further eight contests to go before the medal race next Tuesday.

She said: “I’m gutted to make a couple of mistakes, but I feel like I can actually get into the fight and really give it a go.”

* Oxford-born Mike Lenzly scored on his Olympic basketball debut for GB against Brazil, but limped off in the second quarter after injuring himself and could be out for the remainder of the Games. Britain lost 67-62.

* Henley’s Sarah Thomas helped Great Britain’s women’s hockey team to a 5-3 victory over South Korea, registering their second win of the tournament.