Question: How many seasons did Gregory Allan Williams portray the role of Garner Ellerbee in Baywatch?

Context paragraphs:
Peter Williams (broadcaster): Peter Allan Williams (born 6 March 1954) is a New Zealand television presenter and sports writer.

Gigi Gorgeous: Giselle Loren Lazzarato (born Gregory Allan Lazzarato on April 20, 1992), better known as Gigi Gorgeous, is a Canadian model, actress, and internet personality.

Gregory Despres: Gregory Allan Despres was convicted of the murders of Fred Fulton, 74, and Veronica "Verna" Decarie, 70, of Minto, New Brunswick, Canada, which occurred on April 23, 2005.  On March 5, 2008, the Court found Despres guilty, but not criminally responsible for his actions at the time.

Kim A. Williams Sr.: Kim Allan Williams Sr. (born 1955) is an American cardiologist.  He is a Fellow of the American College of Cardiology and served as its president 2015–2016.  He is currently a trustee of the organization.

Baywatch: Baywatch is an American action drama series about the Los Angeles County Lifeguards who patrol the beaches of Los Angeles County, California, starring David Hasselhoff.  The show was canceled after its first season on NBC, but survived through syndication and later became one of the most watched television shows in the world.  The show ran in its original title and format from 1989 to 1999.  From 1999 to 2001, with a setting change and large cast overhaul, it was known as Baywatch: Hawaii.

Gregory Alan Williams: Gregory Alan Williams (born June 12, 1956) is an American actor and author.  He is known for portraying Garner Ellerbee in "Baywatch".  From 2011 until 2013, Williams portrayed the role of Coach Pat Purnell in the USA Network series "Necessary Roughness."  Williams also appeared on the 2015 ABC series "Secrets and Lies" and is currently on "Greenleaf".

Greg Ellis (rugby league): Gregory Allan Ellis was an Australian rugby league player from the 1950s and 1960s.

Tommy Moore (musician): Born in Liverpool, Moore worked as a fork-lift truck driver and part-time musician.  He first played drums with the Silver Beetles in May 1960, at the suggestion of Allan Williams, and later that month travelled to Scotland with John Lennon, Paul McCartney, George Harrison and Stuart Sutcliffe, when they acted as a backing band for singer Johnny Gentle.  During the tour, he was injured and lost his front teeth when the band's van, driven by Johnny Gentle, had a minor accident.  However, Lennon and the Scottish organiser of the tour took him out of hospital and insisted that he perform with the rest of the group.  After they returned to Liverpool, Moore had already decided that he had 'had enough of Lennon'; When he didn't appear for a gig one night, the rest of the band went round to his flat, and were told by his girlfriend that he had gone back to his steady job at the bottle works.  When they tried to persuade her otherwise, she apparently said 'you can all piss off!' .  He undertook one further performance with the group, before they left for Germany with Pete Best as their drummer in August 1960.

Allan Williams (politician): Louis Allan Williams (June 22, 1922 – February 28, 2011) was the Attorney-General of British Columbia from 1979 to 1983.  He also held the posts of labour minister and minister responsible for native affairs.  Williams died on February 28, 2011 following a long illness.

Greg Gibson (umpire): Gregory Allan Gibson (born October 2, 1968) is an umpire in Major League Baseball who has worked in the National League from 1997 to 1999 and throughout both major leagues since 2000.  Throughout his career, he has worn the number 53 on his uniform.

Supporting paragraphs: Gregory Alan Williams Baywatch
Answer: one