MOOSE JAW, SASK. -- Northern Ontario's Krista McCarville threw a perfect game in a 4-3 victory over Alberta's Laura Walker on Wednesday morning at the Scotties Tournament of Hearts.

Facing two in the 10th end, McCarville made a hit to give up a single for the victory at Mosaic Place. She was 100 per cent for the game while Walker threw at 81 per cent.

Northern Ontario was in a second-place tie with Canada's Chelsea Carey and Saskatchewan's Robyn Silvernagle in Pool A at 4-2. Manitoba's Kerri Einarson led at 5-1.

Carey picked up a single in the 10th end on a measure to edge Nunavut's Lori Eddy 6-5. Prince Edward Island's Suzanne Birt topped Yukon's Hailey Birnie 11-5 and British Columbia's Corryn Brown posted an 8-6 win over Erica Curtis of Newfoundland and Labrador.

The top four teams from each eight-team pool will have their records carry over into the championship round starting Thursday. Walker and New Brunswick's Andrea Crawford were tied in fifth place in Pool A at 3-3.

In Pool B, Ontario's Rachel Homan and Team Wild Card's Jennifer Jones were tied at 5-1. Brown and Birt were next at 4-2 ahead of Mary-Anne Arsenault of Nova Scotia at 3-3.