Andy Murray lost a one-set exhibition match in Abu Dhabi after stepping in as a late replacement for Novak Djokovic.
Murray intended only to practice as he recovers from a hip problem but agreed to replace Djokovic after the Serb withdrew due to an elbow injury.
The Briton lost the first four games against Spain's Roberto Bautista Agut before he was able to hold his serve.
Murray looked better as the match went on, saving three match points before Bautista Agut registered a 6-2 win.
The British number one was forced to end his 2017 season early because of his hip trouble and has not played competitively since Wimbledon.