Is Rory McIlroy the man to beat for major glory at Valhalla rather than Scottie Scheffler?

Rory McIlroy has won on his last two PGA Tour starts but is without a major victory since the 2014 PGA Championship; McIlroy and Scottie Scheffler are the pre-tournament favourites heading into the week at Valhalla; watch the opening round live on Thursday from 1pm on Sky Sports Golf