Triple world champion Tyson Gay will run the 200 metres at the Aviva London Grand Prix.

The American sprint star, who won 100m, 200m and 4x100m relay gold at the World Championships in Osaka two years ago, has already shown he is in terrific form this summer after matching his own US record of 9.77seconds to win the 100m in Rome last week.

Gay has only raced once this season over 200m - when he clocked 19.58 seconds in New York back in May.

That time - the third fastest ever behind Olympic sprint champion Usain Bolt and American sprint legend Michael Johnson - remains the world lead mark this season.

The 26-year-old will take to the track in London in what will be his final outing before the World Championships in Berlin.

Gay said: "The race in London is important for me as a final test for the World Championships. I've only raced once this season in the 200m and I was really happy with that.

"Another 200m fits perfectly into my preparation for Berlin at this time and London will be the place to do that."