McDavid was a force all night as the Senators had no answer for his speed and skill.
"He just took the game over," said Ottawa coach Guy Boucher.
Oilers coach Todd McLellan admitted he’s beginning to run out of accolades for McDavid’s abilities.
"He’s just a remarkable athlete," said McLellan. "Especially the way they responded after getting scored on, that was important. It was great leadership and we talked a lot about this push back, response shifts and he and their line did a tremendous job of doing that. He’s just got so much pace to his game, change of speed, deception, it’s tough to defend."
Trailing 2-0 to start the third, the Senators made it a one-goal game on Duchene’s power-play goal. But the Oilers responded with a goal eight seconds later by Nugent-Hopkins following a great pass from McDavid.
Edmonton then made it 4-1 on yet another great play by McDavid, who set up Rattie for his third of the season. Caggiula scored his second of the night at 6:34, also on the power play.
"I thought we had some guys who did a really good job on (McDavid) early and he had the one goal where he found some open ice, but other than that I thought we kept him in check," said Duchene. "It just shows you that if you give a guy like that a little bit of room he can make you pay."
Ottawa made it 5-2 as Chlapik scored his first NHL goal, tipping a Marian Gaborik shot. With the second assist Bobby Ryan picked up his 500th career point.
McDavid scored his second of the night late in the contest as he walked around Mike Hoffman.
The Oilers took a 2-0 lead five minutes into the second on McDavid’s 35th of the season. McDavid took a pass from Nugent-Hopkins in the slot and beat Anderson high.
Edmonton opened the scoring midway through the first as Caggiula found a loose puck in the crease and knocked it in for his 11th of the season.
Defenceman Christian Wolanin made his NHL debut with the Senators. Wolanin signed with Ottawa on Wednesday after three seasons at the University of North Dakota. His father, Craig, played 695 NHL games and won a Stanley Cup with the Colorado Avalanche.
"It was nice to finally be on the ice," said Wolanin. "I think I was more comfortable on the ice than I have been in my hotel room so it was good to be out there in my comfort zone."
The 23-year-old played 17:09 in his debut and didn’t look out of place.
"It’s clear with the puck he’s definitely an NHLer," said Boucher. "He’s smart, he’s heads up, he’s poised, jumps into the play and has really good speed."
Goaltender Filip Gustavsson, acquired by Ottawa from Pittsburgh in the Derick Brassard trade, arrived Thursday and met the media for the first time. The Swedish prospect will join the AHL’s Belleville Senators on Friday.
"I like playing on the small ice," said Gustavsson. "There’s a bit more speed and I’m looking forward to it.
"I have great confidence right now and my game is really good so I hope I can keep that going here."
Gustavsson, selected in the second round, No. 55 overall by Pittsburgh in the 2016 NHL draft, was playing in Sweden with Lulea HF.
Notes: The Senators were without captain Erik Karlsson (personal) and forward Mark Stone (leg). Ryan Dzingel returned to Senators lineup following a one-game absence after taking a puck to the back of the head last Saturday. Edmonton forward Mike Cammalleri was a healthy scratch.