Reilly Opelka, who defeated Novak Djokovic in the Brisbane International quarters, was trailing 4-1 in the first set when he had to withdraw due to a back injury

Djokovic is in search of his 25th Grand Slam title at the Australian Open, but fell short of the semifinals at his warm-up event.

Novak Djokovic was beaten 7-6 (6), 6-3 by big-serving Reilly Opelka in the Brisbane International quarterfinals

Jiri Lehecka claimed the Brisbane International men's title after Reilly Opelka retired with an injury while trailing 4-1 in the opening set.

Czech tennis player Jiri Lehecka sealed his second ATP title on Sunday after Reilly Opelka was forced to retire in the first set of the Brisbane International final with a back injury. Lehecka led 4-1 when the physically hampered Opelka was forced to stop.

Czech Jiri Lehecka has won the Brisbane International after feelgood story Reilly Opelka retired with a back complaint when trailing 4-1 in the final.