Walker, Newcastle born left back George Marshall joined Southern League Southend United in 1913 from Newcastle City and played both sides of World War One at Roots Hall, before transferring to Second Division Wolverhampton Wanderers for £800 in 1920 with Southend colleague Frank Burrill.
He made his Football League debut at Fulham in August 1920 and played44 matches that season as Wolves’ run in the FA Cup brought them all the way to the Cup Final at Stamford Bridge where they narrowly lost to Tottenham Hotspur in front of King George V.
Marshall played two more seasons for Wolves and after a single goal (in a 2-1 defeat at Bury in April 1922) in 111 appearances, he moved to Walsall in the summer of 1923, but he only played 11 times for The Saddlers the following season.
He briefly joined Reading without making a first team appearance before moving to Bournemouth & Boscombe Athletic, where he made his debut in January 1925 and played 20 times in the second half of the 1924-25 season. He returned to The Midlands and joined non league Darlaston later that year.