London Broncos edged out John Kear's part-time Batley side by a 22-16 scoreline to secure their place in the quarter-finals of the Challenge Cup.
The Londoners overcame awful weather conditions at Mount Pleasant and enthusiastic opponents to grind out a hard-fought victory in a fifth-round tie played in constant driving rain.
Australian half-back Craig Gower led the Broncos' efforts on his 34th birthday as the Super League outfit claimed their first win away from home for almost 12 months to deny Kear, a cup winner with both Sheffield Eagles and Hull, another famous scalp.
The Championship outfit chose to play uphill first and the gamble looked to have backfired when the Londoners scored three tries in a 10-minute spell to open up a 16-0 lead.
Gower's kick was caught in the wind and bounced kindly for winger Jamie O'Callaghan to touch down for the game's first try.
Gower then got second rower Matt Cook through a gap for a try and prop Antonio Kaufusi crashed over from close range for a third which, with Shane Rodney's second goal, made it 16-0.
The introduction of towering forward Alex Walmsley injected fresh impetus into the Batley side and they responded with two converted tries in six minutes to close the gap to just four points at the break.
Centre Danny Maun took Gareth Moore's short pass to go through a chink in the Broncos defence for the first and second rower Mark Applegarth burst through for another after Ben Black supplied the final pass.
With the marked slope in their favour in the second half, the tie was set up for Batley to take the spoils but the Londoners raised their game, with Michael Witt taking over from his half-back partner Gower as the main threat.
Centre Dan Sarginson was held inches short of the line and only a desperate tackle by Batley full-back Ian Preece denied a charging Kaufusi a second try.
Broncos winger Kieron Dixon had a try disallowed for offside as the visitors piled on the pressure and it was no surprise when they eventually extended their lead, hooker Chad Randall burrowing his way over from dummy half on 71 minutes,
Rodney's third goal opened up a 10-point gap, and although Batley gave themselves renewed hope when Preece won the race to touch down Black's kick to the corner, the Super League side held on.