Poplar, London born right half Sammy Frost began his football career with Millwall St John’s, from where he signed for Southern League club Millwall Athletic in 1900. After a season at The Den he was signed by First Division club Manchester City in the 1901 close season, making his Football League debut at Everton in September that year, one of a pair of matches he played for City that month as City were relegated at the season end, but he didn’t play again in The Citizens’ first eleven for a year, when he made the right half berth his own, spending three seasons as their principal right half.
Frost was part of City’s team that immediately won the Second Division Championship in 1902-03 and then won the 1904 FA Cup Final, beating Bolton Wanderers 1-0 in the Final at The Crystal Palace courtesy of a Billy Meredith goal. However he lost his place at the start of the 1905-06 season and although he regained it for 10 matches between November and January, he re-joined Millwall Athletic in the 1906 close season after 3 goals in 112 appearances for Manchester City. He continued to play for Millwall for several seasons until his eventual retirement.