NATHAN ASPINALL continued his dream debut run at the William Hill World Championship as he reached the quarter-finals with a 4-3 victory over Devon Petersen at Alexandra Palace.
Petersen won each of the first two legs on double eight before going on to win the first set 3-1 with a 115 checkout.
The South African ace raced through the second set 3-0 and led 2-0 in the third - but missed three darts to win it in four legs, allowing Aspinall to turn it around and halve the match deficit.
Petersen's excellent finishing from early in the match continued to desert him as Aspinall punished more missed doubles to take the fourth set 3-1.
Aspinall averaged 104 in the fifth set, which he edged 3-2, before a second 115 checkout under pressure helped Petersen clinch set six 3-1.
Aspinall missed a dart at the bull for a 170 finish to double his lead in the deciding set and his opponent landed double 12 to level. The next two legs were shared, forcing a tie-break in which Aspinall won back-to-back legs to progress.
Aspinall - 95.76
Petersen - 90.75
Aspinall - 7
Petersen - 6
Aspinall - 88
Petersen - 115
Aspinall - 0
Petersen - 2
Aspinall - 15/39
Petersen - 16/40