Drysdale currently competes on the European Tour, having graduated through qualifying school for the fourth time at the end of 2008.
He had previously qualified for the elite tour in 2001, 2006 and 2007 through q-school, in addition to graduating directly from the Challenge Tour in 2004, when he finished 12th on the end of season rankings, largely thanks to a sudden death playoff victory over Mattias Eliasson at the Bouygues Telecom Grand Final.
The 2013 season saw Drysdale finish 6th at the Avantha Masters, and 10th at the Johnnie Walker Championship at Gleneagles.
In 2014, a back injury at the start of the season caused Drysdale to pull out of the Nelson Mandela Championship.
At the ISPS Handa Perth International in October, he had to finish in the top 7 to retain his European Tour card for 2015.