Early career
In July 2011, Dieng signed for Grasshoppers from Red Star Zurich. [3]
In November 2012, Dieng made his debut in adult football at the age of 17, for FC Grenchen whilst on loan from Grasshoppers. [4] He signed his first professional contract with Grasshoppers on 1 August 2014. [5]
In 5 August 2014, Dieng was named on the bench in a 3rd qualifying round Champions League match against Lille. [6]
On 2 February 2016, aged 21, Dieng signed for MSV Duisburg on a free transfer but relegation to 3. Liga meant he was released months later without having made any appearances. [4]
Dieng left for a career in England where he went on trial with AFC Fylde, Rochdale and Barnsley. [7]
Queens Park Rangers
On 26 August 2016, Dieng signed for Queens Park Rangers on a free transfer until 2018. [4]
On 3 July 2019, Dieng signed a new two-year deal with QPR, keeping him at the club until 2021. [8]
Loan spells
On 2 December 2017, while playing for Whitehawk (in National League South) on loan, Dieng scored a goal in the 91st minute of a game against Chippenham Town. [9] Going up into the Chippenham box for a late corner, he headed in from 8 yards. [10]
Dieng spent the first half of the 2018–19 season, on loan at Stevenage, [11] making his debut on 14 August 2018 in an EFL Cup match against Norwich City. [12]
On 10 January 2019, Dieng joined Dundee on a loan deal for the remainder of the 2018–19 season. [13]
On 26 July 2019, having still not made a senior appearance for QPR, Dieng went out on loan again, this time joining League One side Doncaster Rovers until 4 January 2020. [14] Dieng made his Rovers debut in an EFL Cup match against Grimsby Town on 13 August 2019. This loan was extended to the end of the season on 3 January 2020, [15] with, at the time, only 3 sides having conceded fewer in the division.
Return to QPR
On 20 September 2020, Dieng signed a new four-year deal with QPR, keeping him at the club until 2024. [16]
Dieng made his first league start for Queens Park Rangers on 26 September 2020, in a 1–1 draw at home to Middlesbrough. [17] Dieng was named QPR's Player of the Month on two occasions during the season, in November [18] and January. [19] On 17 April 2021, Dieng received a red card on the 58th minute after a late challenge on Duncan Watmore in a 2–1 away win at Middlesbrough. [20] Throughout the 2020–21 season, Dieng made 42 appearances and kept 11 clean sheets in his first full season for QPR. [21] At the end of the season, Dieng was named Players' Player of the Year alongside Rob Dickie. [22] He also finished the season having made the most saves of any goalkeeper in the Championship.
Dieng was handed the No.1 jersey for the 2021–22 campaign. [23]
On 13 August 2022 he scored his first goal for the club with a last minute header to equalise away to Sunderland. [24]
Middlesbrough
On July 8, 2023, Dieng completed a transfer for Middlesbrough for a reported transfer fee of £2 million, signing a four-year contract. [25]
In the month of October 2023 he conceded just 1 goal, and was praised by manager, Michael Carrick, for how well he had settled into his new side. [26]
