Williams, 24, made six Engage Super League appearances in 2010. Powell said: “I’ve had to do a fair bit of looking around to strengthen our pack, and Dave fits the bill. He’s a big rangy prop, with a lot to offer.”
Powell is looking for a repeat of his side’s 28-22 win at Barrow last week. He said: “It was the best victory since I’ve been at the club. We were unbelievably busted up.
“Now we can relax a little bit and go to play against Widnes. If we come up with the type of effort that we did against Barrow, then we take some beating.”
The Vikings scored nine tries during last week’s 50-10 win over Rochdale, but Betts said: “I’m more happy about the fact we only conceded two tries.”
On Rovers, he added: “Featherstone are one of the best sides in the competition. It’s going to be a challenge, but we’re looking forward to it.”
Widnes are top of Northern Rail Cup Pool One due to a superior points difference, but a Featherstone win would ensure they finish in first place.