Armour first joined the PGA Tour in 1981 at the age of 21. He has two career PGA Tour victories, winning the 1990 Phoenix Open and the 2003 Valero Texas Open. Armour currently holds the scoring record for best overall score 72 hole score (254), which he set with his Valero Texas Open victory in 2003. Armour finished 110th on the 2007 PGA Tour money list, earning his card for 2008. He finished his year with a win at the non-PGA Tour sponsored Callaway Golf Pebble Beach Invitational, winning $60,000. In 2008, he finished 62nd on the money list to retain his card for 2009 and was the first repeat champion at the Callaway Golf Pebble Beach Invitational.