Stone gave the Senators a 3-2 lead at 7:08 of the third period, knocking home a loose puck in the crease for his 16th goal. He has 12 points (seven goals, five assists) in his past 10 games.
"We've really been struggling on the road and we're trying to get something going," Stone said. "We were aggressive in the third period and didn't allow them anything."
Stone was the first player to realize that Stefan Elliott's shot had ended up slightly behind Howard, not under him.
"He's one of my favorite players, and that sequence is why," Blashill said. "He created the turnover in the neutral zone and then he makes a smart play to finish it."
Tierney scored into an empty net on the power play at 19:42 for the 4-2 final.