Cameron Norrie suffers semi-final defeat to qualifier Mariano Navone at Rio Open

Norrie, the defending champion, struggled physically in the Brazilian heat as Navone, playing in his first ATP semi-final, pulled away to win 6-4 6-2.

Defending champion Cameron Norrie lost in the semi-finals at the Rio Open (Steven Paston/PA) (PA Wire)

Cameron Norrie’s defence of his Rio Open title is over after he was beaten by qualifier Mariano Navone in a gruelling semi-final.

Norrie struggled physically in the Brazilian heat as Navone, playing in his first ATP semi-final, pulled away to win 6-4 6-2.

The pair traded breaks in the opening two games, and then Navone, showing little fear in his first appearance on such a stage, got the break again to go 4-3 up.

Norrie saved break point three times in the next service game, but it was only a temporarily reprieve before Navone took the first set.

The pair traded further breaks at the start of the second set before another slog of a battle in the third game, which saw Norrie save four points on his serve before eventually succumbing.

That proved a turning point as Navone reeled off the next two games to take a commanding lead over a fading Norrie, whose resistance had been broken.

After falling 5-2 down, Norrie received treatment from the physio but got back on his feet to see the game out even though his fate was already sealed.