Andy Murray has overcome a below-par display to book his place in the third round of the Cincinnati Masters with a 6-4 7-5 victory over Mardy Fish.

It was a performance which lacked the rhythm Murray showed on the way to victory in the Rogers Cup last week, but he capitalised on opportunities at key moments in the match to edge past the American, who missed the support he was expected to receive from the locals after heavy rain forced the meeting to be delayed.

Both players were guilty of wasting chances to take control in the opener as they immediately lost their serve after making breakthroughs, and it soon became clear that Murray was perhaps not timing shots from the back of the court as well as he has done recently.

However, Murray converted set point at the first attempt on the Fish serve but his experienced opponent continued to battle impressively to make it difficult for the third seed.

Fish, who has announced that he will retire after the US Open, had two chances to get back on level terms but Murray twice fought back from a break behind.

After clinching a break of serve to force the tie-break, Murray quickly pulled away as his rival's challenge faded and he wrapped up a 7-1 success to set up a meeting with Grigor Dimitrov.