David Ferrer had no complaints following his ATP World Tour Finals defeat against Andy Murray after struggling with his serve at the O2 Arena on Monday.

Home favourite Murray won an entertaining contest 6-4 6-4 on day two of the season-ending tournament in London.

Ferrer produced some high quality tennis, executing the drop shot impressively and winding up some sumptuous forehands from the baseline in a typically energetic display.

But second seed Murray kept the Spaniard at bay and fought back from a break down in the second set to make a winning start in the Ilie Nastase Group.

Ferrer double-faulted eight times and had a first-serve percentage of only 49, which he knew would prove to be costly. 

"I served badly at the end of the first set and also in the second set. When the serve doesn't work against top-10 players it's difficult to beat them," said the world number seven.

"In important moments he was better than me. He played more aggressive than me. At the end of both sets, I didn't play so good."

Ferrer was full of praise for Murray, who produced another classy display on home soil as he attempts to reach the final of this tournament for the first time ahead of playing in the Davis Cup final against Belgium next week.

"He's playing good. He was in the final [at the Paris Masters] last week. He is number two in the world. He's playing very confidently." Ferrer added.

"Also he's in the final of Davis Cup, playing the three matches. So he's having one of the best season of his career, for sure."