William Ruggles MacKenzie (born September 28, 1974) is an American professional golfer who has played on the PGA Tour. MacKenzie was born and raised in Greenville, North Carolina.
He turned pro in 2000.
MacKenzie played on several mini-tours shortly after turning pro. He played on the Golden Bear Tour in 2003 and finished ninth on the money list. The next year (2004), he played the Hooters Tour and finished third on the money list with three wins. He also played on the Nationwide and Canadian Tours.
2005 was his rookie season on the PGA Tour. His first win came in 2006 at the Reno-Tahoe Open in his 47th career start on the PGA Tour. He won the 2008 Viking Classic in a three-way playoff on the second hole over Marc Turnesa and Brian Gay.
In 2013, MacKenzie played the entire season on the Web.com Tour, finished 40th on the money list, and regained his PGA Tour privileges through the Web.com Tour Finals. In the 2014 PGA Tour, he finished second at the Valero Texas Open and fourth at the Valspar Championship.