Having impressed QPR manager Ian Holloway in training,[10] Chair was named as a substitute in club's first round EFL Cup tie against Northampton Town at Loftus Road on 8 August 2017.[11] He replaced Luke Freeman in the 63rd minute of the match to make his first-team debut.[3][11] Chair made his first starting appearance for QPR in a 1–0 defeat against Preston North End at Deepdale on 2 December 2017.[12] He signed a two-year contract extension with the club on 9 February 2018, keeping him at the club until the summer of 2020.[13] He scored his first goal for the club during QPR's final home game of the 2017–18 campaign on 28 April 2018, scoring a volley at the far post as QPR overturned a one-goal deficit to win 3–1 against Birmingham City.[14] Chair made seven first-team appearances during the season, scoring once.[15]