Ireland's preparations for their TikTok Women's Six Nations trip to face England on Sunday have been made even more difficult, with eight of their previous matchday squad unavailable.
It had been expected that Ireland would lose multiple players to the sevens programme for the upcoming HSBC World Rugby Sevens Series in Canada, with confirmation that seven players will now be unavailable, six of whom featured in Round 3 against Italy.
Of the team that started against the Italians, Ireland's centre partnership and back-three combination will all be returning to sevens duty, with Beibhinn Parsons, Lucy Mulhall, Amee-Leigh Murphy Crowe, Stacey Flood an Eve Higgins all taking part in the tournament in Langford.
As well as that, head coach McWilliams will also be without back row Brittany Hogan who featured in all three games so far in the championship, as well as second row Anna McGann.
And in a further blow to McWilliams' side, they will also be without lock Sam Monaghan and back row Aoife Wafer due to injury.
Wasps second row Monaghan (below) had emerged as Ireland's standout player in the opening rounds of the championship, and McWilliams says the injuries come as a real blow.
"We had a really productive camp on Saturday, during which we got through a good body of work both on and off the pitch. Unfortunately we will be without both Sam and Aoife through injuries this weekend," he said.
"David (Nucifora), Aiden (McNulty) and myself have been in regular communication over selection and we feel we have the right balance for this window, knowing that there are further development opportunities coming up for the XVs squad, with plans at an advanced stage for a two-Test Summer Tour in August, and the important qualification tournaments facing the Sevens programme over the same period.
"There are a number of players who have had to be patient during the first three Rounds of the Six Nations and they now have an opportunity to stake a claim for the green jersey.
"We have a good group of players in camp with us now, a nice mixture of experience and players who have impressed me during the Energia All-Ireland League season, and coming off the back of our win over Italy, are determined to finish the Championship with strong performances."
Laura Feely, Laura Sheehan, Mary Healy, Shannon Touhy, Sene Naoupu and the uncapped Leinster pair of Niamh Byrne and Alice O'Dowd have been called up to the squad for the final games against England and Scotland.
England will be heavy favourites against Ireland this Sunday at Welford Road, having averaged more than 60 points per game so far in the tournament, and conceding just 10 points in three games.
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