[2][3] William was one of many workers at lace manufacturers Johnston, Shields & Co in Newmilns sent over to work in the company's newly opened factory (by John Shields and Edward B. Steegmann) in Sant Martí de Provençals (known as La Escocesa), which started production back in 1893, and thus, the family had to move again, this time to Sant Martí.
The rest of the family will return to the United Kingdom at the beginning of the First World War, with the exception of John, known in Catalonia as Joan, who settled in Barcelona.
[2] In May 1895, William refereed football matches held at the Velódromo de la Bonanova on the occasion of the opening of the racing season on 12 May.
[2] [a] At the start of 1900, William and his La Escocesa co-workers set up a football team to pass the time, calling it Escocès FC.
[4] He was the referee of the last match of the first edition of the Copa Macaya, which was one of the most important matches in the early history of Catalan football because it would decide the winner of the tournament between FC Barcelona and Hispania AC, with the latter only needing a draw to win it, and the result smiled at Hispania as they held Barça to a 1–1 draw, with Mauchan disallowing a second goal from Barcelona (scored by John Parsons) for offside, a decision that was heavily contested, with Barça claiming bias refereeing in favor of the organizers of the tournament.