McWilliams made his debut for Morton on 15 August 2009, against Dunfermline Athletic after Bryn Halliwell was injured in the warm-up.

[2] After being released by Morton, on 30 July 2010, Ryan signed for Ayr United on a 1-year deal as back up to David Crawford.

[5] East Stirlingshire traveled to play Rangers on 18 August 2012, where McWilliams earned the Man of the Match award after several point blank and double saves; these helped keep the score respectable as the Shire lost 5–1.

After narrowly missing out on the West Region Championship Ryan continued his stay at Benburb until the summer of 2021 when he decided to leave due to injury.

Ryan then moved on to newly formed West of Scotland Football League 4th division Paisley based side St.Peters.