Usain Bolt safely through 200m heats at Rio Olympics 2016

Usain Bolt took another step in his quest for an unprecedented sprint "triple triple" when he safely negotiated the first round of the 200m on Tuesday.

Bolt won a third successive 100m title on Sunday to set up his bid to repeat his haul of three gold medals in the 100, 200 and 4x100m relay at both the Beijing and London Olympics in 2008 and 2012 respectively.

Bolt, who is desperate to better his 2009 world record best of 19.19sec, clocked 20.28sec in winning his first round heat, easing up a full 50 metres from the line.

American Justin Gatlin, who won silver behind Bolt in the 100m, also looked comfortable as he won his heat in 20.42sec.

Unlike the frosty reception afforded him by a jeering Olympic Stadium crowd before the 100m heats and final, Gatlin was actually cheered in bright sunny conditions. He briefly put his hands together, as if in thanks.

Gatlin`s compatriot Lashawn Merritt, who won bronze in his specialist event, the 400m, on Sunday, also qualified after winning his heat in 20.15sec.

Merritt has the best time of the year with 19.74sec, set at the US Olympic trials in Eugene in July.

Bolt`s season fastest is 19.89sec, set in London last month, but few would bet on the Jamaican not defending his 200m title for a third successive time.