Novak Djokovic came from a set down to beat Andy Murray at the Barclays ATP World Tour Finals in London for his 10th win against the Scot.
World number one Djokovic defeated his US Open conqueror 4-6 6-3 7-5 in two hours and 34 minutes to remain undefeated in the round-robin tournament.
Murray won the first set 6-4 having broken Djokovic in the opening game of the match before successfully holding his serve throughout the remainder. He served out with a love service game for a one-set love lead after 44 minutes.
In the sixth game of the second set the Serbian stretched to dab a volley into the open court for his first break point of the match and the chance to lead for the first time. Murray opted to serve and volley but smacked the ball well beyond the baseline.
Djokovic also served out a love service game to take the match into a third set decider, tallying eight winners en route in his recovery.
Murray was broken again in his second service game and survived a break point later on as he continued to trail the 25-year-old Serb, but saved another break point before he broke his opponent to tie the final set at 4-4 on his serve.
Murray took a 5-4 lead but Djokovic held to stay in the match before breaking back and serving out the match for his second successive win at the O2 Arena, having defeated Jo-Wilfried Tsonga in straight sets on Monday.