Dustin Johnson’s greatly improved wedge play keys big run in 2016

Dustin Johnson enters the PGA Championship with a chance to become World No. 1 by week's end.SPRINGFIELD, N.J. – It was drizzling when Dustin Johnson finished his morning pro-am round during the Northern Trust Open at Riviera this February. His team would finish first that day, but instead of joining his group – which included his future mother-in-law, Janet Gretzky, and his fiancee’s brother, Tristan Gretzky – for a celebratory lunch, there was something he needed to address.

Instead of climbing the tall stairs to the famous clubhouse atop the hill at The Riv, Johnson and his brother/caddie, Austin, veered right off 18, to the practice area. Next to a Trackman that had been set up, he…