Former Huddersfield Town defender believes that the Terriers must make more attacking signings in order for his club to solidify themselves as a Premier League club.
Sinclair, 46, made 42 appearances for Huddersfield between 2007 and 2008 and has seen his former side rise from League One to the Premier League in just a few short years.
They will be looking to avoid relegation once again next year and Sinclair has urged manager David Wagner to consider signing more attacking talent to achieve that goal.
Sinclair has suggested Swansea City forwards Jordan and Andre Ayew as well as West Bromwich Albion striker Solomon Rondon.