LONDON — Usain Bolt opened defense of his Olympic 200-meter title with a comfortable win in the opening round Tuesday, easing up over the final 80 meters to finish in 20.39 seconds.

The Jamaican, who won the 100 meters Sunday night in an Olympic-record 9.63 seconds, will race again Wednesday in the 200 semifinals. The final is Thursday.

Bolt was in the first heat of qualifying, with teammate Yohan Blake and American Wallace Spearmon racing later.