Castleford's Mike Mc Meeken celebrates his try during the 66-10 demolition of Leeds
21 Marcha, 2017, 01:28
Aided by the conditions, Salford did an excellent job of shutting down Castleford's attacking threat.
Powell described it as a "slow game" and added: "We couldn't get any tempo at all".
"We were poor", admitted Powell. John Bolton, from Eccles, said "I can not believe we have just beaten the best team in the league, I am going to sink some tonight!"
Salford pressed strongly, but scored just one try when Ben Murdoch-Masila went over eight minutes before the break. Michael Shenton appeared to have sent Greg Eden over on the left wing, but celebrations were cut short when referee Phil Bentham ruled a forward pass.
"I thought it was an unbelievable finish by Minkin for his try - just awesome - and there was nothing in the game".
Gale's conversion opened a two-score gap which looked like being enough, but Salford dug in and a host of errors pinned Castleford in their own half.
O'Brien levelled the scores with a 67th-minute penalty and, after Eden had come up with a fumble deep inside his own half, kept his nerve with another crucial drop goal.
Three minutes from time Eden knocked on at a tap restart 20 metres out and O'Brien - whose drop goal in last year's million pound match kept Salford in Super League - landed the winning one-pointer in the resulting set.
"We're enjoying ourselves at the moment, but we need to recognise we've got some tough games coming up".
"People had asked me in the week about going all season undefeated but this puts that to bed pretty quickly". Some of the boys have got some wising-up pretty quickly to do.
"I thought Salford were superb".
"We didn't deserve to win". Minikin is a doubt for Sunday's visit of Catalans Dragons due to a shoulder problem and Webster suffered concussion.
Powell said: "It doesn't help when you are having to move people around". It was a bit of an arm wrestle and they just edged it. They really defended us well.
Head coach Watson, who kept marquee signing Todd Carney on the bench as he awaits his debut, said: "There is a lot of pressure and responsibility to drop goals and Gareth stepped up to the plate again". "He's just pleased we got the win".
Full-back Zak Hardaker, who Salford were interested in before the season, then failed to deal with a high kick and in the next set Murdoch-Masila juggled with the ball before getting into his stride 15 metres out from the line and proved unstoppable as he tore over for his second try, which O'Brien converted. Flanagan. Substitutes: Brining, Krasniqi, Kopczak.