Williams has been part of the W-League since the inaugural season but back then she was donning the green as a member of Canberra United.

She was part of the first game Canberra played, which was a 2-1 loss to the Newcastle Jets in the opening round.

However, heading into the 2018/19 season, she didn't know her milestone was creeping up.

"I didn't know until a few weeks ago that it would be my hundredth during this season," Williams said.

"Everyone was like 'You haven't reached 100 yet?'.

"It's kind of crazy because I never thought I would ever get 100 caps in the league," she said.

Unfortunately, the 30-year-old has been made to wait a bit longer despite being the first choice keeper at both Canberra and City.

In 2014, she tore her anterior cruciate ligament (ACL) and the meniscus in the left knee during a game for Western New York Flash in the NWSL. It was the second time she had torn her ACL on that same knee having had a knee reconstruction in 2012. 

Despite these injuries, Williams has become one of the most successful players in the league with three Championships (2011/12, 2016/17 & 2017/18) and two Premierships (2011/12 & 2013/14).

However, one of her favourite memories came with Canberra during the 2011/12 season, where the side went through undefeated.

"The Canberra season where we went through undefeated and then won, that was epic," she said.

The Kalgoorlie-born shot stopper becomes the second player this round to join the 100 club but she also is the first goalkeeper to reach the milestone.

"It hasn't happened to a lot of players and the significance is amazing obviously," Williams said.

"You see other girls from different countries getting their 100th cap and I think to recognise the W-League that is pretty cool," she said.

It hasn't been the best start to the season for City, who currently sit in seventh having just a single win to their name this season.

So a win against the Newcastle Jets would put the cherry on top of the cake for Williams in her milestone match.

"You always go through things in life that mean something to you, to get a win in such a monumental way and personal achievement that would be amazing," Williams said.

"Whilst it is amazing for me as I have been going through the season, to get a win, in general, would be great," she said.

Catch Lydia William's milestone match from 2:30pm at McDonald Jones Stadium or on Fox Sports 505 and SBS Viceland.