Willoughby is a tall and athletic pace bowler who can fire down swinging, left-arm deliveries that many international batsmen struggle to handle.
He has been around for a while and toiled unnoticed by the South Africa national team selectors for six seasons before he was named in the Proteas squad that went to Sharjah in 1999/2000.
He performed admirably but his international career went no further until the South Africa A tour of West Indies in 2000/01.
Willougby grabbed his chance with both hands and claimed 10 wickets at an average of 24.30 in three first-class matches.
The talented seamer made his Test debut against Bangladesh at Chittagong early in 2003.
He was signed by Leicestershire for the 2005 season after Mark Cleary was ruled out with a back injury.
In 2006 he moved to Somerset initially as a Kolpak player on a three-year contract.
He had an excellent season in 2007 as Somerset took the division two title in the LV County Championship.
His 62 wickets - including five five-wicket hauls - paved the way for success and he added a further 11 in the Friends Provident Trophy.
In 2008 Willoughby fell one short of 50 championship wickets, which came at a respectable average of 28.