Chris Neil, Bobby Butler and Jason Spezza also scored for the Senators while Colin Greening and Nick Foligno added two assists each. Ottawa scored on four consecutive shots spanning the first and second period to break it open and send the reeling Penguins to their fifth straight loss.
Evgeni Malkin scored his 17th goal of the season for Pittsburgh but couldn't stop the Penguins from matching their longest losing streak in two years. Brent Johnson made just five saves on eight shots before being pulled early in the second period in favor of Marc-Andre Fleury.
Pittsburgh, a Stanley Cup favorite after Sidney Crosby's brief return in November, is now eighth in the Eastern Conference at the season's midway point.