Leyton Pennant continued their dismal run of form as they crashed out of their second cup competition in four days on Tuesday night.
Lunn, of Leatherhead, scored the opener for the lowly opposition, setting off an avalanche of goals in an astonishing 13-minute spell.
Before they knew it, the Lilywhites were three goals down, thanks to Webb’s strike and another from Lunn.
The tie looked over, but Scott Kennedy fired in a reply after Tony Dixon’s shot was blocked and Billy Read pulled back a second with his shot from the edge of the area.
Pennant sensed a comeback, but five minutes before the break, they paid the price for letting their powers concentration weaken.
Firstly, a corner was met unchallenged by defender Edwards to make it 4-2 and, on the stroke of half-time, it became five when Lunn completed his hat-trick to effectively end the contest.
In the 70th minute, Read gave his side a glimmer of hope with a cool finish, but another failure to defend a set-piece meant that Leatherhead added their sixth soon after.
The last word went to the visitors, with Read’s penalty making him the second player on the night to score a hat-trick. Sadly for him, it meant very little in the scheme of things.