Jamaican sprinter Asafa Powell has confirmed that he is to face compatriot Usain Bolt in consecutive weeks as the pair build up to London 2012.
Powell has now signed to feature in the 100m race in Oslo on 7 June, having previously agreed to perform only in Rome on 31 May.
Bolt, the Olympic champion over 100m and 200m, had already agreed to race at both Diamond League events.
Powell, 29, is expected to be one of Bolt's main rivals at the games.
Powell made his British indoor debut at the Birmingham Grand Prix on 18 February, but was upstaged in the 60m by compatriots Lerone Clarke and Nesta Carter, who forced him to settle for third.
Powell's personal best in the 100m is 9.72, with Bolt still holding the world record of 9.58, set at the world championships in Berlin in 2009.