Jason Day makes flying start at BMW Championship

Jason Day continued his fine form with an incredible start to the BMW Championship on Thursday.

The world number three, winner in three of his past five starts including the US PGA Championship, was 10 under through 17 holes when inclement weather led to an early finish in Illinois.

FedEx Cup leader Day holed an eagle, nine birdies and a bogey at the Conway Farms Golf Club to sit four shots clear.

American Daniel Berger fired a six-under 65 to be outright second, a shot ahead of a group of four players including Jordan Spieth.

Spieth, who is through 17, produced one of the highlights of the day with a hole-in-one at the 196-yard second.

In the same group as two-time major winner Spieth, Day was in fine form.

Starting on the back nine, the Australian made four birdies on his first six holes before his only blemish at the 17th.

Day responded with a birdie at the 18th, an eagle at the par-four first and four more birdies before weather cut his round short.

Spieth was unable to match the 27-year-old, going through his first nine in even par before the ace at the second.

The world number two holed three birdies after that to sit at five under.

Berger finished his round strongly to be second, while Brendon Todd, Kevin Chappell (through 16) and Justin Thomas (13) are alongside Spieth in a tie for third.

Matt Kuchar and Scott Piercy have finished their rounds and are tied for seventh at four under, alongside Bubba Watson (through 13), Kevin Na (14) and George McNeill (12).

World number one Rory McIlroy made a solid start to the event, sitting at three under through 12 holes.