Newtown's hopes of progressing in the Swalec Bowl evaporated with a 19-5 away defeat at Llanidloes In atrocious conditions.
Llani will now face Division Four side Vardre on February 19 in the last 16, the furthest the club has ever progressed in a WRU cup in its history.
After dominating the first half Llani's pressure forced Newtown into conceding a lot of penalties with full back Dan Short taking three in difficult kicking conditions to go in 9-0 at half time.
The second half continued in the same vein and Llani were rewarded with two tries from replacement prop Luke Murphy and flyhalf Adam Pryce.
Llani then sat back a little and had to absorb a lot of pressure from Newtown in the last 15 minutes, resulting in a try by their wing Andrews at the death.