Watertown's Erika Kelly scored both goals in the Raiders' victory over Arlington, Tuesday at Victory Field.
The season opening victory extends the two-time defending state champions' unbeaten streak to 47 games, but coach Eileen Donahue said the team did not play its best game.
"We had a great preseason, we played all the best teams," Donahue said. "Now the games count and we didn't do it the way we wanted it to be done."
Some of the Raiders came to play, Donahue said, including Kelly, and fellow co-captain Lauren Giordano, as well as Lauren Sutherland and goalie Kayla Carlson.
Arlington had few chances on net, and Watertown scored twice. All in all, Arlington head coach Colleen Flynn said she was happy with her team's performance.
"We did an excellent job defending," Flynn said. "They are the defending state champions."
The play of Spy Ponder's junior goalie Carolyn Woodin particularly caught Flynn's eye.
"She did a phenomenal job," Flynn said. "She stood on her head at times."
Arlington's record dropped to 1-1, following a 2-1 win over Wakefield.
The game marked the season opener for Watertown, which had two games canceled due to rain last week.