Rory McIlroy's lead evaporates as world number one Dustin Johnson signals intent

Rory McIlroy's overnight lead disappeared in the space of three holes as Dustin Johnson signalled his intent to remain world number one in the WGC-Mexico Championship.

McIlroy's only previous appearance in 2017 had come in the South African Open in January, when he lost out to Graeme Storm in a play-off despite suffering from what was subsequently diagnosed as a stress fracture to his ribs.