After three successive defeats and with a host of first-choice players missing because of injury or suspension, any win would be welcome and the fact it came against Hull was merely icing on the cake.
Saturday, when Tigers visit Huddersfield Giants, will be two years since Radford was sacked by Hull following a heavy home loss to Warrington.
They will make the short trip to John Smith’s Stadium in high spirits after a rare home win, only their third since the start of last season.
Aided by one of the fastest tries in Super League’s history and a terrific hat-trick from recalled winger Greg Eden, Tigers came out on top 33-26 in an 11-try thriller in front of a crowd of more than 10,000 at Wheldon Road.
It was a deserved success for the hosts, who were brilliantly marshalled by an out-of-position Paul McShane.
With Niall Evalds having joined the injury list, Gareth O’Brien went to full-back and McShane was at scrum-half, where he had an outstanding game.
Tigers also had prop George Lawler at hooker and two youngsters, Sam Hall and Cain Robb on the bench, so were very much second-favourites against a Hull side who had won two of their opening three games.
Hull, however, fell well short of the standard they had set against Salford eight days earlier, making a host of errors and conceding some costly penalties, particularly in the early stages.
Tigers had been waiting for something to go their way this season and it did, right from the kick-off as Daniel Smith scored inside the opening 10 seconds.
Jake Connor made the catch and turned the ball to Ligi Sao. He dropped it and Smith was there to pick up and touch down.
O’Brien added the conversion and Castleford had made the dream start, which got better on eight minutes when Danny Houghton was sin-binned for a high tackle on McShane.
It may have been a reflection of their poor opening to the campaign, but rather than keep the pressure on against 12 men, Tigers took two points from the subsequent penalty, through O’Brien.
Castleford were agonisingly close to increasing their lead further when, after Hull had been penalised for taking too long over a scrum near their line, O’Brien fired out a pass towards Eden.
Making his first appearance of the season, on the left-wing, he would have scored if he had caught it, but fumbled the ball into touch.
Another error in the same channel, by centre Jordan Turner this time, paved the way for Hull’s first score, on 27 minuteConnor counter-attacked, then following a scrum around half-way, Houghton played a one-two with Andre Savelio before darting between the posts for his 50th Hull try, which Ben McNamara improved.
However, Hull consistently turned the pressure back on themselves through errors and penalties and so it proved moments after the try.
They were penalised in possession inside their own half and on the last tackle, Jake Trueman picked out Eden and he forced his way over from close range.
Hull shot themselves in the foot yet again when the restart went out on the full and Castleford scored in the set from the penalty, Trueman again being the provider, this time for Cheyse Blair on the other side of the field.
O’Brien added the goal, but - incredibly - Hull responded immediately with what was almost a carbon copy of the game’s first try.
This time, the visitors’ restart was spilled by Derrell Olpherets and McNamara picked up to send Josh Griffin over. The goal from McNamara cut Tigers’ lead to 18-12 at half-time.
The flurry of tries continued after the break, Tigers adding two more to go three scores clear. O’Brien threw a dummy a scooted through a big gap in the defence, following a drop out forced by clever kick from McShane.
The full-back then turned provider with the final pass to Eden to score his second try, on 51 minutes, after Robb, who played as replacement hooker and Trueman had handled.
Neither touchdown was converted and Hull looked to be getting back into the game with tries either side of the hour mark, through Adam Swift - who dived over at the corner from Griffin’s pass - and Connor Wynne, off Connor’s kick behind the line.
With McNamara converting the first, the gap was down to four points, but Eden’s stunning hat-trick score turned the tide again.
Trueman began the move with a pass to Turner, he supplied Alex Sutcliffe and the ex-Leeds man sent Eden dashing clear. The winger dummied to pass inside and got past Connor for a brilliant try which O’Brien improved from the touchline.
Hull refused to give in and Jamie Shaul’s unconverted try put them back within six points with as many minutes left, but O’Brien capped a fine game with a drop goal to finally seal the win.
Castleford Tigers: O’Brien, Olpherts, Fonua, Turner, Eden, Trueman, McShane, Matagi, Lawler, Smth, Blair, Sutcliffe, Wesdterman. Subs Hepi, Martin, Hall, Robb.
Hull: Connor, Swift, Griffin, Wynne, Shaul, Reynolds, McNamara, Sao, Houghton, Satae, Savelio, Lane, Fash. Subs Lovodua, Evans, Brown, Johnstone.
Referee: Robert Hicks (Oldham).