PGA Championship: Dustin Johnson: Taking route 66 was easy

Dustin Johnson admitted an opening 66 in the US PGA Championship was as easy as he made it look, but the hard part will be converting that into an overdue first major title after numerous near misses.

Johnson carded an eagle, five birdies and a solitary bogey to set a testing clubhouse target as a strengthening wind made conditions difficult for the later starters.

At six under par, Johnson held a two-shot lead over a seven-strong group which included playing partner Jason Day, with English pair Justin Rose and James Morrison another shot back on three under.