Yamamoto made it 2-0 at 15:10 of the second period. Hart saved Evan Bouchard's shot from the right face-off circle but couldn't control the rebound, and Yamamoto reached into traffic and slid the puck past him.
The forward missed the previous game, a 2-1 loss at the Carolina Hurricanes on Sunday, because of an undisclosed injury. It was his 11th goal of the season, tying his NHL best from 2019-20.
"He's an important piece of our team," Oilers coach Jay Woodcroft said. "'Yamo' gives us energy on the forecheck, he's a dogged backchecker, just relentless on the backcheck. ... He has a high hockey IQ and is willing to pay a price to score. You don't go to where he went to to get that goal unless you're brave, unless you're willing to pay that price, and he sure was tonight."
McDavid scored into an empty net at 18:20 of the third period for the 3-0 final.
NOTES: McDavid leads the NHL with 77 points (29 goals, 48 assists) and Draisaitl is second with 76 points (37 goals, 39 assists). … McDavid has scored 15 points (six goals, nine assists) during a six-game point streak against the Flyers. ... Oilers defenseman Duncan Keith was plus-2 in 15:56 after missing nine games with an upper-body injury. … Edmonton forward Brad Malone had three hits in 9:22 in his 200th NHL game, his first since April 6, 2019. He was recalled from Bakersfield of the American Hockey League on Monday. … Koskinen's six shutouts tied Dwayne Roloson for seventh in Oilers history. … Edmonton is 17-0-0 when scoring first. … Philadelphia is 1-for-17 on the power play in its past six games (5.9 percent). … It was Edmonton's win at Philadelphia since March 3, 2016. The Oilers lost their previous three games here (0-2-1). ... It was the first time in seven games Edmonton did not allow a power-play goal; it was 16-for-24 (66.7 percent) on the penalty kill in its previous six games.