Canberra United keeper Lydia Williams.

Canberra United keeper Lydia Williams. Photo: Jeffrey Chan

Strikers win games, but defenders win championships.

That's the mantra Canberra United is preaching as the club begins the mission for its second W-League title in the past three seasons.

Matildas goalkeeper Lydia Williams and the impressive back-four defenders will need to be at their best again in Saturday's semi-final against Brisbane Roar at McKellar Park.

United's rock-solid defence has been the key to collecting the premiership, conceding just eight goals from its 12 games this season.

Vice-captain Ellie Brush has established a formidable partnership in the centre of defence with newcomer Catherine Brown, while skipper Nicole Sykes and young gun Sally Rojahn have been consistent performers at left and right back respectively.

In a sign of the depth in the squad, Georgia Yeoman-Dale and Grace Field filled in admirably when Brush and Rojahn were rested from last week's 2-1 win against Sydney FC to avoid picking up a fourth yellow card for the season.

Williams has played her part, keeping a club-record six clean sheets from her 11 appearances.

''With strikers you win games, but with defenders you win championships,'' Williams said.

''We wanted to concede as little goals as possible, they're desperate defenders and have done their job at important times. So far I haven't had many goals put against me, that's a credit to them.''

The role Williams has played in her return to United can't be underestimated.

The 25-year-old featured in the club's first four seasons and was in the goal for its maiden championship in 2011-12.

A torn anterior cruciate ligament in her knee while playing in Sweden in 2012 forced Williams to miss all of last season as United missed the finals.

Williams found the mental battle to return as tough as the physical pain, using the motivation of regaining her Australian jersey as a driving force in her recovery.

''The first stepping stone to World Cups and Asian Cups was to have a really good W-League,'' Williams said.

''I was really excited to get back training with the national team, but to have a good season with United was a big motivation to know I can perform like this day in and day out. Physically, you might feel well with an ACL, but mentally it takes a lot to get back to where you were.''

Meanwhile, United's W-League semi-final won't be shown live on television, with the ABC instead showing the women's Australian Open golf championship on Saturday.

It will be broadcast live on ABC Radio. A one-hour highlights package of the W-League will be shown on ABC TV at 6pm.

SATURDAY

W-League semi-final: Canberra United v Brisbane Roar at McKellar Park, 3pm. Live on ABC radio from 3pm. TV: Highlights on ABC, 6pm.