Born in
Bedlington, Northumberland, Trewick started his career at
West Bromwich Albion and played nearly 100 league games for the club during the late 1970s. He also played six times in the UEFA Cup during the
1978–79 season, scoring one goal against
Galatasaray. During West Brom's visit to China in 1978 he entered football history by, in reply to a question about the
Great Wall, remarking "Impressive, isn't it? But once you've seen one wall, you've seen them all!" Trewick maintains the TV documentary gave the wrong impression and he was merely joking. He was offered the role of manager at Hereford, which he accepted on 24 April 2009, after
Graham Turner announced his resignation. Trewick offered his resignation after failing to win any of the first seven League games in the 2009–10 season, but was persuaded to stay on by Turner. The club remained in the lower reaches of the division, with their lowest ever Football League gate of 1,266 on 23 February at home to Northampton. On 8 March 2010, Trewick was sacked, with chairman and former manager
Graham Turner taking the job on a temporary basis. Following his sale of Hereford United, Turner became manager of
Shrewsbury Town and hired Trewick as a "Senior Coach". ==References==