OTTAWA — The Pittsburgh Penguins extended their winning streak and put a dent in the Ottawa Senators’ playoff hopes.

Tomas Vokoun made 34 saves to earn his 300th career win and Dustin Jeffrey had a goal and an assist to lead the Penguins to their seventh straight victory, 3-1 over the Senators on Monday night.

With the loss, the Senators dropped into eighth place in the Eastern Conference.

“They were better than we were from start to finish,” Senators coach Paul MacLean said bluntly. “They were harder at the nets ... at both nets than we were and executed way better than we did.”

Jarome Iginla and Tyler Kennedy also scored, and Brenden Morrow had two assists for the Penguins, who have already clinched first place in the Eastern Conference.

Penguins coach Dan Bylsma gave credit to his 36-year-old backup goalie’s milestone performance.

“The numbers are significant. I think he’s the 28th guy to get to 300 wins and those are very impressive numbers as a goaltender. I thought he was very good in the net tonight and he was strong,” said Bylsma, who also reached a milestone with his 200th NHL victory.

“When you look at career wins for coaches, I’m not sure where 200 wins is. It’s a long way to go to some of the other good coaches, but certainly I’m happy to have gotten it and I got the puck.”

Matt Cooke added an assist in his first game against Ottawa since his skate blade sliced the Achilles tendon of Senators defenseman Erik Karlsson on Feb 13. Karlsson was expected to miss the rest of the season following surgery, but the defending Norris Trophy winner is back practicing and could return to the Ottawa lineup soon.

Patrick Wiercioch scored and Craig Anderson stopped 21 shots for the Senators (23-16-6), who have dropped two straight.

Ottawa started the night in seventh place in the conference and could have leapt over the sixth-place New York Islanders. Instead, the Senators are now eighth, tied on points with the seventh-place New York Rangers.

The Penguins, who have already clinched first overall in the Eastern Conference, were without Sidney Crosby, Evgeni Malkin and Kris Letang, because of injuries and illness, while No. 1 goalie Marc-Andre Fleury was in Pittsburgh with his wife expecting their first child.