Andy Murray overcame the challenge of Ivan Ljubicic to book his place in the semi-final of the BNP Paribas Open.

The Scot, seeded four, recorded a battling 7-5 7-6 (8/6) victory over his Croatian opponent in two hours eight minutes.

Murray looked the more aggressive from the outset, breaking his opponent in the opening game to race into a 2-0 lead.

Ljubicic, who was taken the distance by Igor Andreev yesterday, fought back to level the set at 3-3 only to be let down by a series of errors in the 11th game.

The key moment in the second set came in the ninth game when Ljubicic, serving at deuce, was unhappy when Murray made a successful challenge.

The Croatian was sure the line judge had correctly called a shot out and the umpire even admitted he agreed with him, but could not overrule the technology so the point had to be replayed.

Ljubicic lost his serve on the next point and Murray was left to serve for the match at 5-4.

But he broke straight back as the set went to a tie-break, Murray holding his nerve to progress.

In the women's event, unseeded Anastasia Pavlyuchenkova progressed to the last four with a 7-6 6-4 win over Agnieszka Radwanska, the seventh seed from Poland.

The contest featured 11 breaks of service as the Russian prevailed in one hour 35 minutes.