Hughes picked himself up a brace after the break, capitalising on a pair of one-on-ones against over-run goalkeeper Simon Borich.
Cooper and Jack Chaney also got their names on the scoresheet in the 7-0 romp.
Coach Duncan Lowry, who will fly out on the morning of Sunday's Chatham Cup tie to attend a family wedding in Ireland, was happy his side had got through the match without any great concerns.
"All boxes are ticked, goals ticked, unfortunately I won't be around next week but I've done my job," he said.
"It's the committee's decision to play on the Sunday - it would have been nice to be here for it.
"It's always going to be difficult to hand anything over. What we've created here is second to none and we'd been here 18 months last week.
"We think we are doing the things right. We build from the dressing-room out and the dressing-room has been great all year."
The local side, unbeaten at home this season, is pulling out all the stops in its preparation for the knockout fixture.
Captain Sam O'Regan, who was stood down from the match against Warkworth after his accumulation of yellow cards, travelled away on Saturday to check out the form of his side's next Chatham Cup opponents.
Belvedere Group Tauranga City United 7 (Connor Taylor, Jordan Culpepper 2, Jerahl Hughes 2, Andrew Cooper, Jack Chaney) Warkworth AFC 0