Rory McIlroy insists there is still 'a lot of work to be done' despite sharing the early lead at the PGA Tour's BMW Championship. The world No 2 worked with coach Michael Bannon before firing six birdies in an opening-round 64 at Bellerive Country Club. McIlroy holed a 15-foot birdie at the fourth and recovered from a wayward drive to take advantage of the par-five eighth, then ended a run of pars by rolling in from eight feet at the par-three 13th.

The Masters champion converted from five feet at the 15th before delivering a birdie-birdie finish to get to six under, lifting him into a share of the clubhouse lead with Gary Woodland, Wyndham Clark, JJ Spaun and Chris Gotterup.

Woodland set the initial target despite finishing his 64 with a bogey, having made a hole-out eagle on the 11th, while Spaun also dropped a shot at the last to slip back to six under, as Clark rallied with five birdies in his last six holes to share the lead.

Pre-tournament favourite Scottie Scheffler won by eight shots last week but is eight strokes back after a nightmare start, where four bogeys in the first seven holes saw him stutter to a two-over 72 and leave him tied-44th of the 50-man field.