Stingrays coach Carmelina Moscato believes her in-form squad will face their biggest test to date when they host title rivals Sydney University at JJ Kelly Park on Sunday.
Both clubs have already put themselves in the title conversation through the opening five rounds of the campaign.
Uni sit one spot above the Rays on the NSW NPL Women's 1 ladder and are undefeated to start the season. Sydney have four wins and a draw to their name and have conceded just twice heading into round six.
"We know they are going to be highly structured and very organised as they have been in the past," Moscato said.
"They have threats across every line on the pitch. From strikers to midfield and even in defence, they have dangerous players there.
"This will be one of our toughest games of the season there is no doubt about it."
This will be one of our toughest games of the seasonCarmelina Moscato
Both teams are coming off massive wins last weekend.
Illawarra shocked last season's grand final winners Manly United in a determined 2-1 win while University hammered North West Sydney Koalas 5-1.
The clash on the weekend will be somewhat of a grudge match after University ended Illawarra's title dream last season with an emphatic 6-1 victory in the first round of finals.