Phil Mickelson yesterday hinted at the extent of his determination to relaunch the assault on Tiger Woods’ hegemony when breaking the habit of a lifetime and dumping one of his cherished inner circle.

The news that he has replaced his long-term coach, Rick Smith, with Butch Harmon had been expected in the golfing world, but still the fairways were abuzz with the appointment.

There were a few reasons for this other than Mickelson’s hitherto renowned loyalty to those close to him. Harmon was, of course, Woods’ swing mentor before being abandoned unceremoniously and many will see this as a direct challenge to the world No 1. Although the split between Mickelson and Smith appears to have been amicable - the pair have vowed to remain “great friends” as well as business partners - the jilted teacher did have one parting shot.

“Butch probably wants to get back at Tiger,” Smith told Golf Digest, after learning that Mickelson had been spotted working with Harmon on the range at recent tournaments. “And maybe he thinks he can do that through Phil.”

Mickelson’s decision makes perfect sense on the playing front. The driving game of the three-time major winner has, at best, been erratic and Mickelson made no secret of the fact that thisaspect of his game will be Harmon’s priority. “Butch is one of the very best teachers in the world,” he said, after announcing his new man to work alongside short-game specialist Dave Pelz. “I’m fortunate that he has agreed to spend time working with me, particularly on my driving.”

As the pair try to eliminate the errant tee-shots that ultimately put paid to his title defence at the Masters three weeks ago, they will start off at this week’s Byron Nelson Championship in Texas. Harmon is expected to be rather more vocal than Smith, who was viewed by many as a “yes man” and admitted that he had failed to persuade Mickelson to shorten his glaringly over-extended backswing. “Butch isn’t going to sugarcoat it,” said Fred Couples, who was a Harmon student for five years.