Tanni Grey-Thompson will be up before the sun today as she goes into her own personal D-day aiming to become Great Britain's most successful Paralympian of all time on the final day of athletics at the Athens Paralympics.

The Redcar-based wheelchair racer, already a 100m gold medallist in the T53 class, is just one gold away from beating fencer Caz Walton's record of ten career Paralympic gold medals as she goes for glory in both the 200m and 400m.

Grey-Thompson revealed she will be up to check out of the Paralympic Village at 4.30am as her first final - the 400m - takes place at 10.50am Greek time and she has to be at the Olympic Stadium at least two hours before the race.

''Tomorrow is a big, big day for me and it's going to be an early start. We have to check out at 4.30am to get here for the first race,'' she said.

''I pity the person who has to be around me then because I always get a little queasy before I race.''

The 35-year-old is strongly favoured to win the 400m, but is unlikely to out-pace Canada's Chantal Peticlerc, already a quadruple Athens gold medallist, in the more difficult open category 200m.

Grey-Thompson produced a season's best time of 58.09 seconds to qualify comfortably for the 400m, but is wary of the threat posed by Sweden's Madelene Nordlund.

The Swede set a new Paralympic record of 57.37 in the other heat and Grey-Thompson said: ''She's going to be the strongest one. She's got a slow start but then picks up strongly about 250m so the only thing I can do for the final is just go flat out from the start and try to hang on.''

In the 200m Peticlerc - a T54 athlete - is in a class of her own.

The Canadian qualified fastest in a time of 29.14secs with Grey-Thompson in the same heat clocking 30.75.

''It was a good fast race but it's pretty tough when you are in a semi against Chantal. She's been knocking chunks out of the world record,'' said Grey-Thompson.

''But in a way it was a good thing because it dragged me through in a fast time. That will get me a better lane tomorrow.

''To be honest I don't see anyone beating her so really it's a race for silver and bronze.

''It's hard for me competing in a different category but I was determined to do all four distances.

''Two finals tomorrow is not ideal but we've known about it for a while and I've been planning for it.''

David Roberts crowned one of the individual performances of the Games by claiming a stunning fourth swimming gold medal in the 50m freestyle in dramatic fashion.

The Welshman recovered from a poor start to beat team-mate Matthew Walker to the finish by the slenderest of margins in a thrilling race which ended in a British one-two and saw Roberts eclipse his Sydney achievement of three gold medals.

Roberts' triumph came on a golden 'super Sunday' for the British team which yielded a trio of gold medals, including a third successive Games team gold for the dominant Team GB equestrian squad and an unexpected archery gold in the women's team event.

Ironically, the major threat to Roberts' goal was team-mate Matthew Walker, who led the race until the last few strokes when Roberts fought back to beat Walker by a fingertip.

The times confirmed the closeness of the race with Roberts finishing just three one hundredths of a second ahead of Walker in a time of 28.77 seconds.