Bornnin Glasgow, Priestley started his career with St Johnstone in Scotland before moving South of the border to join Chelsea in May 1920 at the age of nineteen. He spent eight years with the what West London club until 1928 when he signed for Grimsby Town, who would go on to be promoted to Division One the following year.
Chelsea
Priestley didn't make his debut for the Blues until a year after he joined the club, playing in a 0-0 draw away at Blackburn Rovers on 2 May 1921. He wouldn't make another appearance for Chelsea until Boxing Day 1922, missing the 1921/22 season completely. Turning out for the Pensioners in a 4-0 win at Nottingham Forest, Priestley made a further 22 appearances during the season, scoring his first goal for the club in a 3-0 win against Bolton Wanderers in front of a crowd of 20,000 at Stamford Bridge. The 1923/24 season saw Priestley make 42 appearances for Chelsea, scoring twice in victories against Middlesbrough and Manchester City, though he was unable to help the London club stave off relegation to the old Division Two. In the following season, Priestley would again feature heavily for Chelsea as the side finished 5th in Division Two, missing out on promotion by 10 points. The 1925/26 campaign proved to be more fortuitous for the Scottish Half Back as he quadrupled his goal tally from the previous year, despite making only six more appearances in all competitions for Chelsea, helping them to a 3rd-place finish in the league come the end of the season. Priestley bettered his scoring record the following season, having his most prolific year for the Blues with 7 goals in 44 appearances. He netted twice from the penalty spot in a 2-1 win over Clapton Orient on New Year's Day 1927 and scored twice again as Chelsea beat Bradford City a month later on 5 February. Though he only made 18 appearances in his last season on the King's Road, Priestley still pitched in with four goals, netting his last double in a 5-2 win against Bristol City at Stamford Bridge. This would be Chelsea's only victory after January 1928 with Priestley in the team as the side finished 3rd in Division Two, missing out on promotion once again.
