Van Riemsdyk pulled the Flyers within 2-1 at 12:00 on a breakaway.
Martin Fehervary extended the lead to 3-1 at 13:16 when he received a pass from Nic Dowd, deked around defenseman Ronnie Attard in the left face-off circle and slid a backhand between Hart's pads.
Eller made it 4-1 at 6:39 of the second period, scoring on a wrist shot from the left circle off a pass from Anthony Mantha on the rush.
"It appeared like we were ready to start," Yeo said. "It looked like we had good energy off the hop, and obviously turnovers fed their game and as they started to roll we didn't respond to it."
Sheary gave the Capitals a 5-1 lead at 15:30 when he was left alone in front of the crease, took a pass from Evgeny Kuznetsov and lifted a backhand past Jones.
Irwin made it 6-1 at 3:31 of the third period on slap shot from the point, his first goal since Dec. 6, 2018, for the Nashville Predators.
"I think [secondary scoring is] important any time of the year," Irwin said. "Obviously we rely heavily on our top guys every night, and they produce every night. For us to chip in, even if it was late goals, it always feels good. It was a great team effort."
Eller made it 7-1 at 5:59 on the rush, and Hathaway increased the lead to 8-1 at 12:42 on a deflection.
After van Riemsdyk cut it to 8-2 at 16:26 on the power play, Larsson made 9-2 at 17:32 with a power-play goal.