Wood, 12 points clear at the top of the National League, started odds-on to knock out the Latics, who are in the bottom four of League One.

But Wigan, who beat Manchester City in the 2013 final, defied their ranking as 3-1 outsiders by chalking up their first away win of the season in the FA Cup, League or League Cup – and handing Wood their first home defeat of the campaign.

Wigan looked in command from the start as Bradley-Paul Burrowes drove his shot into the side netting from the left of the box and Christian Saydee’s drive forced home keeper Ted Curd into a diving save.

The Latics went ahead in the 11th minute when Saydee’s smart pass across the box found Mellish, who fired home.

Wigan went 2-0 up in the 36th minute. Mellish was tripped 25 yards out and Fox stepped up to smash an unstoppable free-kick into the top left corner.

Wood started the second half with a flourish, but it was all over in the 74th minute when Fox headed home Max Power’s corner from the left.