Murray satisfied with Del Potro workout

Andy Murray was given a tough workout in his opening match at the ATP World Tour Finals in London on Sunday but eventually saw off Juan Martin Del Potro in three sets, 6-3 3-6 6-2.

The British number one has now been cut to 11/4 in Stan James outright betting to finish off the season in style, with the US Open champion now available at 22/1.

Murray took early control of the match but Del Potro, who has suffered with a wrist complaint since his surprise win over Roger Federer at Flushing Meadows, gradually grew in stature.

The Argentine amost turned the first set around after losing the opening five games, but carried that momentum into the second and his two break of serves were enough to tie the match.

However, Murray recovered his composure to break immediately in the decider before calmly recording an opening win and was happy with his afternoon's work.

"It was always going to be tough but I played well. I started really good, and he came back into it but I stayed tough in the third set," he told BBC Sport.

"The key was I started serving better in the third set and then started getting some free points on his serve. That was the difference."

Murray will next be in action on Tuesday in his second match of Group A, and will play either Roger Federer (5/2 favourite in Stan James outright betting) or Fernando Verdasco (33/1).

Group B gets underway on Monday with Rafael Nadal (8/1 in the outright betting) taking on Robin Soderling (16/1) in the first match, before Novak Djokovic (11/4) plays Nikolay Davydenko (10/1) in the evening.