He said, "The Celtic league has always been a great competition to be involved in, from its inception right through to the Magners era. It's certainly become a competition that people have stood up and taken notice of. It's a league of quality teams and world-class players, which is testament to the way the league has grown.
"It's here at the Dragons that I was given the opportunity to continue playing in the league and I have grown as a player at Rodney Parade. It's great to be achieving this honour as a Dragons player and I'm also proud to be the first Scottish player to have achieved this league milestone."
Andy makes his 100th league appearance just seven days after Adam Black became the first player in Celtic league history to reach this milestone. Head Coach Paul Turner added:
"As with Adam Black, Andy is a player that I've known from a young age. He's a player that I tried to sign at Bedford when he was seventeen, so it's ironic that I'm sat here with him, later on in his career, as his achieves this league milestone.
"Andy has always been an intelligent and quality rugby player. He's conscientious and sets his own high standards and we're grateful to have him here at the Dragons."
Both Andy Hall and Adam Black are set to appear against Leinster on Saturday.
Dragons: Kevin Morgan; Gareth Wyatt, Paul Emerick, Gareth Maule, Richard Fussell; Ceri Sweeney, Andy Williams; Adam Black, Steve Jones, Rhys Thomas, Adam Jones, Peter Sidoli, Jamie Ringer, Richard Parks, Michael Owen
Replacements from: Ben Daly, Lee Harrison, Andrew Hall, Phillip Dollman, James Harris, Lewis Evans, Richard Mustoe, Jason Tovey, Wayne Evans