|Full name||Gwilym Thomas Mainwaring|
|Date of birth||24 January 1941|
|Place of birth||Port Talbot, Wales|
|School||Eastern School, Taibach|
|Rugby union career|
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Nurtured in his village team of Taibach RFC, Mainwaring was a regular member of the Aberavon RFC team before his first cap in 1966-7 season against Scotland at Murrayfield. He played in all of the Welsh games of that term.
In the following season, he was one of four Aberavon RFC players who played against the touring All Blacks (the others being fellow second row Max Wiltshire, centre Ian Hall and debutant full-back Paul Wheeler). His final test was against England in 1968.
He captained Aberavon RFC in the 1969-70 and 1970-1 seasons playing on until the club's centenary season of 1976-7.
During his career he formed a formidable club second row partnership firstly with Max Wiltshire and later with Allan Martin, both fellow internationals.
After retirement he became a selector at Aberavon RFC. His mother was the famous Mrs Mainwaring, a vociferous supporter of Aberavon and whose humour (delivered from the stand) made her popular throughout Wales.