RIO DE JANEIRO (AP) — With the offense struggling, Maya Moore and the U.S. women’s basketball team turned in a stellar defensive effort to dispatch Canada.

Moore scored 12 points, and the Americans clinched the top seed in the group with an 81-51 win over Canada on Friday.

The Americans (4-0) had been scoring at a record pace, topping 100 points in each of their first three contests – the first time a team’s done that at the Olympics. But they couldn’t get into an offensive rhythm for the first 20 minutes against their northern neighbors.

The U.S. was out of sync for most of the first half, throwing the ball away on fast breaks and missing open shots. Canada, which already had sealed a berth in the quarterfinals for the second consecutive Olympics, wasn’t intimidated. The teams had played an exhibition game before the Olympics started and Canada lost by 40, never recovering from a slow start.

In this game, it was the U.S. that struggled early. The Americans only scored 18 points in the first quarter, their lowest scoring output in any period in Rio. Canada only trailed 18-16. That’s when the U.S. turned up its defense. For nearly 10 minutes, the Americans held Canada without a basket and slowly extended their advantage.