Dimitrov downs Simon in Brisbane

Bulgaria's Grigor Dimitrov has beaten fifth-seeded Frenchman Gilles Simon to reach the Brisbane International second round.

Dimitrov claimed the win on Pat Rafter Arena 6-3 7-6 (12-10) after a marathon tiebreak in which Simon saved match point five times before finally falling.

It's the first win in five attempts for 2013 Brisbane finalist Dimitrov against Simon.

Unseeded world No.28 Dimitrov, whose pop star girlfriend Nicole Scherzinger watched from the stands, will next meet the winner between American Steve Johnson and Serbia's Viktor Troicki.

Australian Sam Groth will be in action on Monday night against Korea's Hyeon Chung with the winner to face third seed Marin Cilic in the second round.