The BBC pundit has heaped praise on the 23-year-old midfielder.
Indeed, Newcastle signed Shelvey for £12 million earlier this month, as reported by BBC Sport, and Sinclair thinks he will offer the Magpies something different in the way of his creativity in midfield.
Sinclair is quoted as telling 90min.com by the Chronicle: "I think that Jonjo Shelvey was a good signing, I think he’s going to bring a little bit more creativity and a mix-up to them, because I think one of the problems that they had was that they played the game too much like a 5-a-side team, with too many short passes."
Newcastle are without a game this weekend as they were knocked out of the FA Cup by Watford in the last round.
The extra time in training (or time off) should benefit the Magpies as Steve McClaren can get the likes of Shelvey, Henri Saivet and Andros Townsend more accustomed to life at St James' Park.
Newcastle still need a new striker and have gambled a little bit with the names they've picked so far. But at least they've adopted a proactive approach, rather than taking the risk of waiting to see if their relegation rivals simply lose more games than them.