On his return from a biceps injury suffered in a pre-season game against Hull KR, the back-row was thrust straight in for Saturday’s 35-20 success over Warrington Wolves.
Foster, 27, fully played his part as Daryl Powell’s Castleford marched on to Wembley where they will face St Helens next month.
Talking to The Yorkshire Post, the former Leeds Rhinos player claimed: “It was fantastic.
“After the frustrations of the injury, to go out there and get the win in the style we did, and to get through to the final, it was just unbelievable.
“It certainly feels like I’ve gone from one end of the spectrum to the other. We were always trying to get me so I was ready for that game just so Powelly had options.
“I went to see him at the start of the week and said that myself, our physio Matty Crowther and conditioner Jamie Bell all agreed that I was prepared and ready to go if he needed me.
“He said he’d hang on, though, because, coming back from injury, he probably needed someone who could do more minutes, which is what I thought he might end up saying. But, as it happened, Cheyse Blair then went down with a bit of a niggle and, with George Griffin not getting his ban overturned either, I found my way in...
“It was ten weeks after the injury and everyone – the lads, the medical team, surgeon – have all been great helping me get back.
“I came through it fine and am just delighted to see us at Wembley.”
In the end, the combative Foster also delivered on game-time – he played 50 minutes rather than an expected 30 – and he hopes to be able to feature again when Castleford host Hull FC in Super League on Thursday.
“It’s a short turnaround and I’m not sure what the team is but I’ll certainly be putting my hand up,” he said.
Castleford have lost their last three games in Super League to fall off the pace but, with Foster being one of eight players returning against Wolves, he believes they are ready to start pushing up the table.
“It’s a massive game for us,” said Foster, who scored Castleford’s only try when they lost the 2017 Grand Final against Leeds.
“We need to get back to winning ways in Super League. We’ve had some under-par performances and we need to be up there at the back end of the year.
“But, after that semi-final display, I’m sure we’ll be confident.”
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