Liverpool have agreed a £75m fee to sign Southampton centre-back Van Dijk on January 1, which will make him the most expensive defender in the world.
But McGuinness, who spotted the Dutchman at Groningen and was responsible for his move to Celtic in 2013, believes the Reds have got more than just a defender in Van Dijk.
The former Celtic scout would watch Van Dijk practice his set pieces in training and reckons the 26-year-old will offer Liverpool another option from free kicks.
Van Dijk’s ability to play out from defence will also benefit his new club.
McGuinness told BBC Sport: “One thing that fans in England will not have seen too much is his ability from set pieces which is very good.