The Bishop Auckland-born defender went straight into the Heed's starting XI for their game against Guiseley and played the full 90 minutes of a 1-0 victory in the Vanarama National League.
And, after winning the sponsors' man of the match award, 20-year-old Williams earned praise from manager Neil Aspin who told his club's official website: "I thought he was excellent considering he only came this morning.
"A big plus was the fact that his attitude was first class. He showed tonight he's a good player, a good footballer. He's got good quality on the ball. He had a good debut."
Meanwhile in the Carabao Cup, Sean Longstaff made his Blackpool bow at Wigan. He played the whole game but the Tangerines lost 2-1. Ivan Toney didn't feature for Wigan.
Alex Gilliead started for Bradford in their first round tie against Doncaster. He came off after 64 minutes, with the scores level, but the Bantams ended up losing 3-2 after Ben Whiteman scored with three minutes left.
Photograph: Dan Cooke