Murray through to semis

Andy Murray booked his place in the semi-final of the Sony Ericsson Open after Andy Roddick pulled out during their clash in Miami with injury.

The first set was going with serve when Roddick required treatment, handing the Scot an easy path to the last four in Florida.

Murray will now have a day of rest before facing either Novak Djokovic or Rafael Nadal.

Despite the presence of Nadal in Miami, Roger Federer's exit offers Murray hope of a first ATP Masters to add to the two titles he has claimed so far in his career.

In the crowd for the brief quarter-final was Brad Gilbert, the coach who oversaw Roddick's rise in the tennis ranks and is now guiding Murray towards the top 10 in the world.

Just like he did with Roddick's game prior to him winning the 2003 US Open, Gilbert has been ironing out the cracks in Roddick's game and the results have been impressive so far.

The 19-year-old was guilty of a slow start when he faced Paul-Henri Mathieu in the previous round, but he looked to assert himself straightaway against Roddick with a forehand winner in the opening point of the match followed by a delicate drop.

Murray, 12th in the world rankings, then had two break points in the second game of the opening set but his American opponent blasted his way out of trouble with his powerful service game.

The match initially went with serve but Roddick was struggling with his injury niggle and he required off-court treatment at 4-3, the world number three appearing to be feeling his upper thigh and buttock.

ATP trainer Bill Norris tended to Roddick in the dressing room and the American was able to continue but his first contribution after the resumption was shanking a smash into the net. Murray seized his chance, breaking Roddick immediately, but the American was unable to continue and was forced to withdraw at 5-3.