Tottenham Hotspur old boys (see Ian Crook, Gary Brooke, Ian Culverhouse and Mark Bowen ) seemed to be popular at Carrow Road in the late 1980s. John had made 28 senior appearances for Spurs before joining Norwich in July 1990 for £300,000.

Born in Walthamstow, East London in June 1968, John's footballing talents were identified at an early age as he represented both Essex and London as a schoolboy. He joined Tottenham, his local club, as an apprentice in 1984 turning professional in July 1985. His league debut came on the 12th May 1986 at Upton Park but a serious back injury limited his development.

John's determination saw him recover and even get capped by England at Under-19 level against Brazil. In March 1990, he played alongside his brother Andy against Crystal Palace, thus becoming the first brothers to play together for Spurs since the Steel brothers in 1912. However he was never a first team regular and became disenchanted with life at White Hart Lane.

Norwich paid Spurs £300,000 in July 1990 for him after a tribunal rejected Tottenham's valuation of him at £750,000. Whilst more expensive than the other former Spurs at Norwich, Dave Stringer appreciated the fact he could play anywhere along the back four.

John made his Norwich debut at home to Sunderland in August 1990. He displaced Paul Blades from his place in the defence and finished the season with 36 appearances. The following season saw Blades restored to prominence after Polston earned Stringer's displeasure when he failed to turn up for a pre-season friendly.

Under Mike Walker, John established himself as a regular in the defence, making 39 appearances in the aforementioned 1992/93 campaign. John consistently made 30 or more league and cup appearances for the next four campaigns. He played in four of Norwich's UEFA Cup matches in 1993, including their first match against Vitesse Arnhem for which he was captain.

Ever present for the first seven games of the 1997/98 season, he performed poorly in the 4-0 home defeat to Charlton on 17 September 1997 and was dropped. He would never start a game again in a Norwich shirt. Subsequent injuries prohibited a return to the first team squad until the end of March 1998. Four appearances as substitute followed but these would be Polston's final matches in yellow and green. John had played 263 times for Norwich, scoring 12 goals.

John was given a free transfer in May 1998 as the club could no longer justify his Premiership level wages. Despite speculation linking him with a move to Southend United, he joined Robert Fleck and Scott Howie at Reading on May 20th 1998.

John announced his retirement at the beginning of April 2001. He never recovered from a knee injury and had spent most of his 3 years at Reading injured - making just 22 appearances. Whilst waiting for an opportunity move into coaching, John worked as a personal trainer and offers body massage and sports injury treatment. His website can be found at www.jppersonaltrainer.com

John's first steps into management came towards the end of September 2002 when his former Tottenham teammate Mark Stimson asked John to join him at Ryman leaguers Grays Athletic as assistant to Mark who would be player-manager. Polston would run the show from the bench when Stimson is on the pitch. John has since parted company with Grays.

In addition to his personal trainer work, John also works at the Teikyo Japanese School near Slough

In December 2015 he joined the coaching staff at Hellenic League side Binfield.