LONDON (AP) — Saturday marks the end of the Usain Bolt’s career.

The Jamaican great is looking for one more gold medal in the 4×100-meter relay at the world championships.

The relay heats are set for early Saturday. If everything goes according to plan and no batons are dropped, it will also mark the final duel between Bolt and American rival Justin Gatlin, who beat the Jamaican in the 100 final last weekend.

Also, British runner Mo Farah will compete in his last race on the track at a major championship when he goes for a fourth straight world title in the 5,000. He won a third 10,000-meter gold on the first day of the championships.

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