By David Ljunggren

OTTAWA (Reuters) - Sidney Crosby notched two goals and two assists as Stanley Cup champions Pittsburgh tightened their grip on their NHL playoff series with a 7-4 win over the Ottawa Senators on Tuesday.

Also in the East, Jeff Carter scored twice in Philadelphia's 4-1 win to put the Flyers 3-1 up in their best-of-seven series and leave the New Jersey Devils on the brink of elimination.

In the West, Henrik Zetterberg scored two goals to help Detroit to a 3-0 victory over the visiting Phoenix Coyotes to tie their series at 2-2.

Crosby and Matt Cooke stunned Ottawa by scoring twice in just 12 seconds early in the second period to put the Penguins up 3-0.

Pittsburgh, who have a 3-1 lead, can wrap up the series in their own arena on Thursday.

Crosby's dominant performance lifted his post-season total to 11 points, the best in the playoffs overall.

"We're being rewarded for good work ... everything's going the way we want it to," he told reporters, playing down his four-point game.

"You get chances and they go in. That's the way it works. You can do the exact same thing other nights and the puck doesn't go in," he said.

Pittsburgh dominated from the start and it was no surprise when Evgeni Malkin scored a power play goal 11:50 into the first period.

Ottawa goal tender Brian Elliott, under siege with 13 saves in the first period, came apart in spectacular fashion in the second, allowing Crosby and Cooke to score at 3:47 and 3:59 respectively.

Crosby then banged in a quick second, prompting Ottawa to pull Elliott and replace him with Pascal Leclair.

The Senators recovered with two quick goals through Chris Neil and Daniel Alfredsson but their hopes of a comeback were dashed by sloppy defense that allowed Maxime Talbot to score a short-handed goal.

"It's not over. A lot of teams have come back from 3-1 down. There will be no quitting," said Leclair.

Ottawa coach Cory Clouston complained about what he said were officiating discrepancies but said his team needed to be better at handling adversity.

Matt Cullen and Jason Spezza scored the other goals for the Senators while Chris Kunitz and Jordan Staal replied for Pittsburgh.