Despite kicking off with a 180, Long only managed an average of 75.33. It was enough to beat his Northern-Irish opponent, however, as 'The Clonoe Cyclone' ended up averaging 74.45.
Both players lacked consistency in the first set, but a 83-finish on the bull saw Mansell take it. A strong 127-finish from his Canadian opponent then levelled the match as both players continued to struggle.
Long had the better of the play as he took set three. The North-American then missed three match darts in set four, but after Mansell missed double seven to send the match into a deciding set, Long kept his cool and booked his place in round two.
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William Hill World Darts Championship
Saturday December 15
Afternoon Session (1230)
Richard North (92.82) 3-2 (85.99) Robert Marijanovic (R1)
Mickey Mansell (74.45) 1-3 (75.33) Jim Long (R1)
Josh Payne v Jeff Smith (R1)
Max Hopp v Danny Noppert (R2)
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