They sit bottom of Super League with just one win in their first five games and, though they came close a week ago, losing 13-12 at Wigan, he is ready to start shaking things up.
“Some players have been told in no uncertain terms this week that we need to see a spike in their performances,” admitted Radford, as they prepare to host Catalans Dragons this evening.
“I’d like to think those players will knuckle down and find some form as soon as possible, because that is what is needed.
“The bare minimum Friday is we produce the effort of last week because that effort got us very close to winning a few games.
“The detailed areas of the game are what will now get us over the line if we can back that effort up.
“But we need to start winning games; that’s the only focus.”
A points difference of minus 18 hints at how competitive Hull are, but the table does not lie.
“We are reminded a lot of where we are in the league, and rightly so,” continued Radford, who is set to give a debut to former Wakefield and St Helens utility forward Stuart Howarth.
“It is a strange one though as in this environment and in this group there is a lot of belief that we are not far off at all and those results could easily have gone the other way.
“But we cannot afford to get 15 rounds in and keep saying if only, if only – we know we have to start picking points up.”
Hull will hope to capitalise on Catalans’ short turnaround given the French side were also in East Yorkshire on Sunday when they were embarrassed 50-20 by a rampant Hull KR.
“We have some games coming up that fall in our favour with Catalans on a short turn around and then we have a week’s preparation for Castleford,” said Radford.
“It’s now or never for us, I suppose.
“The players have lost none of their confidence and that’s a good thing.
“If we were disillusioned or the confidence was going it would be harder. We have to just use our smarts a little more and turn those close defeats into positive results.”
The Airlie Birds are without a raft of players including full-back Jamie Shaul, centre Setaimata Sa (back) and utility Richard Whiting (broken hand).
Meanwhile, Jansin Turgut has gone on a month’s loan to Doncaster following Howarth’s own return from their partner club.