Mattie Pollock

Pollock was a trainee with Leeds United up until under-15 level, where he was considered a midfielder.

Grimsby Town

Pollock joined Grimsby Town on a scholarship in 2018 after being scouted playing as a defender for his father's team, Polton Allstars. He was called up to the first-team bench by manager Michael Jolley for the first time in October 2018. Pollock made his professional debut on 29 December, coming on as a 52nd-minute substitute for Martyn Woolford in a 2–1 win at Exeter City following a red card for centre-back Alex Whitmore. He turned professional in February 2019 and upon signing a 2+1⁄2-year deal said that "my ultimate ambition is to be the best central defender in the world and play at the highest level I can". Pollock was given his first start for the "Mariners" on 13 August 2019, in a 1–0 victory over Doncaster Rovers at Blundell Park. He scored his first goal for Grimsby in a 1–1 draw with Carlisle United on 24 October 2020.

Watford

On 27 May 2021, Pollock joined Watford on a five-year deal for an initial fee of £250,000. On 30 August 2021, Pollock joined Cheltenham Town on loan for the 2021–22 season. Pollock scored his first goal for Cheltenham in the FA Cup first round against Gillingham on 6 November 2021. He also scored in the replay win on 16 November, earning Cheltenham a spot in the second round and praise from manager Michael Duff. Pollock made his Watford debut on 23 August 2022 in a 2–0 home defeat to MK Dons in the second…

As of match played 1 January 2026

Born in Redhill, Pollock was brought up in Middlesbrough, where he attended the Nunthorpe Academy.

He is the son of former Middlesbrough and Manchester City midfielder Jamie Pollock, and younger brother to professional footballer Ben Pollock.