Kyrou made it 2-0 at 5:12 of the second period. Nick Leddy kept the puck in at the left point and passed to Kyrou, who skated through the slot and scored on the forehand.
"I just tried to keep the puck in and create some time, and [Kyrou] did the rest," Leddy said.
Athanasiou cut it to 2-1 at 7:19 when he took a pass from Max Domi and skated in alone on Binnington.
O'Reilly's short-handed goal at 8:08 restored the Blues' two-goal lead. He moved in on a 2-on-1 with Noel Acciari and shot it past Soderblom from the left face-off circle.
"It was a good play by him, picking that pass off and then to go the other way," Berube said. "It's just a great play."
Athanasiou scored his second of the game on the power play to make it 3-2 at 9:35 when he skated up the right wing and snapped a wrist shot from the circle past Binnington. It was his fifth goal of the season.
"Obviously you're always looking to improve," Athanasiou said. "Come in every night and try to help the team, do what I can, whether it's on one end of the ice or the other. Just grow as a player every day and just try to get better.
"When you're down and you get a couple of goals, you kind of get the momentum going. At the end of the day, we gave a little too much up tonight and couldn't fight back."