Duff, last year's beaten finalist, had to come from 4-5 down to claim the opening set 7-5 and then took the second 7-4, despite having to take a break because of the flu bug he has been suffering from.
Bantock fought back to keep the game alive taking the third 7-1, but Duff dominated the fourth, winning 7-2 in seven ends to record victory.
"It was a very hard game. Considering it was Mark's first appearance in Preston he played exceptionally well and produced a lot of good pressure bowls," Duff said.
England's Gary Smith also survived a scare before edging through with a four-set win over the Hong Kong qualifier Tony Tong. Smith dropped the opening set 5-7, but quickly hit back taking the second in just three ends. The No 13 seed turned around a 5-2 deficit in the third set to win it 7-5, and then cruised through in the fourth.Reuse content