England’s Justin Rose is one shot off the lead after starting the defence of his Turkish Open title.
Ireland’s Paul Dunne leads on seven under after the first round in Antalya, with Rose and 2016 champion Thorbjorn Olesen a shot further back.
Dunne’s compatriot Padraig Harrington, who could be Rose’s Ryder Cup captain in 2020, is also on six under.
Rose, 38, will return to the top of the world rankings if he makes the first successful title defence of his career.
He spent two weeks as world number one after finishing second in the BMW Championship in September and is currently second to American Brooks Koepka.
Dunne set the pace on five under after 10 holes before Harrington briefly shared the lead with Finland’s Tapio Pulkkanen, who finished the day on three under.
Dunne, currently ranked 105, birdied two of his last four holes to complete a round of 64 while Rose birdied the 18th to join Harrington and Denmark’s Olesen on six under.