Hull, hoping to lift the Cup for a third successive year, were eventually beaten 25-22 by the Super League leaders but only after an epic fight against the favourites who will now face Catalans Dragons for a place at Wembley.
“I’m disappointed we got beat but unbelievably proud of the team,” said Radford, who lost loose-forward Dean Hadley to an ankle injury in the first minute and was down to 11 men at one point following two yellow cards.
“The lads had nothing left at the end and they were running on fumes. As a coach sometimes all you can ask for is that effort and I got that today.
“The commitment they have shown is great and they kept showing up for each other time and time again.
“We matched them in every department. We just kept going at them and never let down. There was certainly no lack of effort.”
Referee Ben Thaler sin-binned captain Danny Houghton (crusher tackle) and Danny Washbrook (use of knees) towards the end of the first period in a spell where Hull’s 12-10 advantage was turned into a 22-12 deficit.
Masi Matongo was also yellow-acarded in the second period for a late hit but Radford refused to elaborate on his thoughts about the decisions.
He added: “It’s irrelevant - we get them we get them, we don’t we don’t.
“I can’t control (the decisions) or have may influence on that.
“But I think there was one and possibly two penalties against us for our back chat. I can have an impact on that but I can’t have influence on the ones I can’t control.
“The other ones you have to kop them.”