Kelly's Fredericton rink defeated China's Bingyu Wang 9-5 to improve its tournament-leading record to 5-0.
"The Chinese were very defensive to begin with and we went along with that as we checked out the ice," said Canadian third Kristen McDiarmid.
"In the second half, we decided to put a few more rocks in play. We utilized the free guard zone, with central guards and then came around. The change of tactics caught them and they got into a little trouble."
Canadian skip Andrea Kelly is off to a 5-0 start at the world junior curling championships in Italy. (CP Photo)
Canada trailed China for five ends before scoring three in the sixth end and stealing singles in the seventh and eighth frames to take control of the match.
Sweden's Stina Viktorsson sits second in the women's standings with an unblemished 4-0 mark.
In other women's action from Sunday, Norway edged Switzerland 7-5, Denmark beat the United States 8-7 and the host Italians doubled Scotland 6-3.
Women's play resumes Monday.
Canadian men win one, lose another
The Canadian men weren't as fortunate as Kelly's rink Sunday. Kyle George's Regina squad split its two Sunday matches to move to 3-2 on the tournament.
Canada opened the day with a 10-8 loss to Scotland before rebounding with a 9-6 win over Korea in the evening draw.
"We played better as a team tonight," George said.
"The boys played well, which took the pressure off me a lot. It meant I could play better shots. "The Koreans were difficult and sticky. In fact they got a shot in the first which I thought was impossible."
In the first game, Scotland burst out of the gate with a quick three points in the opening end before stealing a single in the second to grab a 4-0 advantage. George counted three in the third to get back into the game and stole two in the sixth to tie things at 6-6.
Scotland eventually earned the win by blanking the ninth end before scoring two with last-rock advantage in the 10th frame.
George's rink got off to another sluggish start against Korea, surrendering a deuce in the first end. However, Canada was eventually able to take control of the match by scoring two points in each of the second, fourth, sixth and eighth frames.
Canada (3-2) now sits in a four-way tie for third place with Denmark, Switzerland and Sweden.
Scotland leads the standings with a perfect 4-0 record, while the U.S. is second at 4-1.
In other men's play in the morning, Sweden edged Germany 3-2, Switzerland beat Denmark 5-2, and the U.S. defeated Norway 6-3.
Denmark dumped Italy 8-6, the U.S. pounded Germany 10-3 and Sweden beat Switzerland 8-5 in the evening draw.
with files from Canadian Press