TRURO, N.S. - Calgary's Pat Simmons and St. John's, N.L.'s Brad Gushue both won their opening round-robin matches at the Grand Slam of Curling Masters tournament on Tuesday.

Simmons, the reigning Brier champion, scored two in the eighth end to dispatch Shawn Adams of Halifax 7-3.

Gushue, meanwhile, used singles in the second, third, fifth and sixth ends to double up Toronto's John Epping 4-2.

On the women's side, Switerland's Silvana Tirinzoni scored four in the third end and held on for a 7-6 win over Sweden's Margaretha Sigfridsson.

Winnipeg's Kerri Einarson edged Eve Muirhead of Scotland 7-6 and Halifax's Mary-Anne Arsenault defeated Anna Sidorova of Russia 5-3.

Round robin action continues through Friday.