Morrison competed as a member of the Brazilian team in the 4 × 200 m freestyle relay at the 2008 Summer Olympics in Beijing. Despite missing out the individual spot in the 200 m freestyle, he managed to place fourth at the annual Maria Lenk Trophy in Rio de Janeiro (1:49.04) to earn a selection on the relay team. Teaming with Rodrigo Castro, Nicolas Oliveira, and Lucas Salatta in heat one, Morrison swam the third leg with a split of 1:49.35, but the Brazilian team had to settle for last place out of sixteen registered nations in 7:19.54.