Shelvey is said by Sky Sports to be on the verge of completing a £12 million move from Swansea City to Newcastle, with the midfielder currently travelling to Tyneside to discuss personal terms.
The England international could become Newcastle’s second signing of the January transfer window, following the arrival of Henri Saviet yesterday, and Cascarino feels he would be a good addition.
"He has got a lot to prove, and McClaren needs to find someone who can do what Shelvey can do," Cascarino said. "There aren’t many players available [who can do that].
"McClaren is hoping that he will be an impact player for him. Even if he comes, and has a fantastic time for six months, he could keep them up. I can see why Newcastle have gone for that type of move."
According to a report in the Daily Mail, Newcastle boss Steve McClaren has promised Shelvey a prominent role his squad.
The 24-year-old has fallen out of favour at Swansea, but the Magpies want him to be a first team regular as soon as he arrives on Tyneside.
McClaren has reportedly promised that Shelvey will become Newcastle’s main creator, and that he will be played in his favoured position of central midfielder.
The Magpies are currently sat in 18th position in the Premier League table, two points adrift of safety.