Ronnie O'Sullivan bowed out of the Coral World Grand Prix at the first hurdle, losing 4-2 to Marco Fu at Cheltenham.
Defending champion O'Sullivan took the first frame with breaks of 68 and 51 but fell 2-1 behind before levelling the contest with a 77.
He was well placed to win the fifth frame but slipped up and Fu produced a run of 66 to move within a frame of victory, wrapping up a surprise success with a 91-0 scoreline in the sixth.
The Hong Kong player will face Barry Hawkins in the second round after 'The Hawk' beat Ryan Day in a repeat of the 2017 final.
Welshman Day took the first frame with a break of 127 but the champion of two years ago hit back strongly, producing knocks of 130 and 143 on the way to a 4-1 win.
Also into the last 16 are Stuart Bingham and Mark Allen.
Bingham was quick out of the blocks against Zhao Xintong, going two frames up on the back of breaks of 131 and 102, then moving to within a frame of victory.
Although Zhao got on the board with a 61, Bingham - beaten finalist in 2016 - wrapping up s 4-1 triumph in the next frame.
Allen won 4-2 against Gary Wilson, finishing the contest with a clearance of 78. He will face either Martin O'Donnell or Ali Carter in the second round.
