Scotland's John Higgins beat Australian Neil Robertson 4-1 in the final of the Bulgarian Open.
Higgins, 38, won 25,000 euros (£21,240) by clinching the title in Sofia.
World champion Ronnie O'Sullivan, playing in his first tournament outside of England in 15 months, lost 4-2 to Higgins in the semi-final.
However, he later changed his mind, saying he could not afford to quit once more and picked up 6,000 euros (£5,100) for reaching the final four in Bulgaria.
O'Sullivan, who last played in a tournament outside of England in March 2012 in the China Open in Beijing, beat Michael Wild, Michael Leslie, Ian Burns, Mark Davis and Mark Williams before his defeat by four-time world champion Higgins.
The Scot also defeated 2005 world champion Shaun Murphy on his way to the final.
Robertson took the opening frame, before breaks of 60, 73, 118 and 82 gave Higgins the victory.
The Bulgarian Open was the first of eight competitions on the European Tour and the best-performing players will then qualify for the Players Championship Grand Final in March.
John Higgins 4-1 Neil Robertson
Neil Robertson 4-3 Barry Hawkins, John Higgins 4-2 Ronnie O'Sullivan
Neil Robertson 4-2 Jimmy Robertson, Barry Hawkins 4-1 Scott Donaldson, John Higgins 4-2 Fergal O'Brien, Ronnie O'Sullivan 4-0 Mark Williams
Neil Robertson 4-1 Anthony Hamilton, Jimmy Robertson 4-2 Anthony McGill, Scott Donaldson 4-1 Matthew Stevens, Barry Hawkins 4-1 Nigel Bond, John Higgins 4-0 Shaun Murphy, Fergal O'Brien 4-1 Stuart Carrington, Mark Williams 4-1 Sam Baird, Ronnie O'Sullivan 4-2 Mark Davis.