Lehner, starting for the second time in eight games, is 4-2-1 and made a couple of big saves with a minute to go in the third period with the Predators pressing.
The Senators (9-5-4) are 5-1-3 at home.
"It was ugly," said Senators forward Bobby Ryan about Ottawa’s first period, when it fell behind 1-0 on a power-play goal by Nashville’s Shea Weber. "Somebody said [the first] was the worst period we played all year, and we’re only down one. It was kind of a positive in the intermission. Guys responded."
Nashville coach Peter Laviolette gave No. 1 goaltender Pekka Rinne the night off and started backup Carter Hutton for the third time. It was his first start since Nov. 4 when he made 23 saves in a 3-1 loss at the Winnipeg Jets.
Hutton, who made 16 saves, is 0-2-1. He faced 12 shots in the second period as the Senators turned up the tempo.
"[The second period] was a tough period, not a good period for us," Laviolette said. "The first period we played the game we wanted to play. The third period we played the game we wanted to play. We had lots of quality scoring chances. We didn’t give up a whole lot. In the second period we gave up enough to get beat tonight. We played 40 great minutes and 20 minutes we wish we could have back."
The Senators were off since a 4-2 loss at the Calgary Flames on Saturday which end a three-game road trip.
"We hadn’t played in a few days, and I think they had a little more speed than us coming out," Lehner said. "I think we made it difficult for ourselves, putting the puck in the wrong spots, but I think we came out in the second and third and played the right way, really worked at it. We tried to outwork them and that’s what paid off in the end."
Two of the Senators three goals in the second period came at even strength against one of the best 5-on-5 team in the league.
Ryan, on the power play, and Chiasson each scored his fifth goal of the season, and defenseman Jared Cowen scored his first to build the lead.
Ryan took a pass from Erik Karlsson and fired a shot through a screen to the stick side at 6:17 to tie the game 1-1. It was the Senators' ninth power-play goal at home this season; they had 16 last season.
Chiasson deflected a shot by Ottawa defenseman Cody Ceci at 12:18 to put the Senators ahead. The goal came after Cowen was able to keep the puck in the Predators zone.
Hutton said he thought the play was offside.
"Half of [the puck] came out [over the line]," Cowen said. "Maybe I just had a biased opinion. I heard [the Predators] screaming and yelling about it. But I thought it was in."
Cowen was stopped by Hutton seconds before he scored at 14:24. Senators forward Milan Michalek did the work on the goal, grinding along the boards against Predators defenseman Roman Josi and forward Mike Ribeiro before emerging in the right-wing corner with the puck and threading a cross-ice pass to Cowen. He took a couple of strides and beat Hutton with a shot to the glove side from near the left faceoff dot.
Cowen has a goal and three assists in his past five games.
"It always feels good to put some more points on the board, kind of add to your game," Cowen said. "It’s funny, when you start getting a couple they seem to start coming in bunches. Hopefully it happens now, and hopefully it goes the rest of the year."
Hutton took responsibility for the loss.
"It’s frustrating," he said. "I felt good, but in this league if you give up three, it’s frustrating. When I’m not playing that often, I’ve got to be sharper. I settled in, but they capitalized. They’ve got some good players and I thought Lehner did a good job.
"You don’t play that often, you have to be better. You still have to get wins when you play. I’m a competitive person and I want to be able to help my team win games when I’m called upon. Tonight I didn’t get the job done."
The Predators scored the only goal of the first period on the power play at 3:17 when Weber fired a one-timer past Lehner's glove. The goal came with Senators forward Colin Greening in the penalty box after a cross-checking penalty in front of the Nashville net.
Greening was in the Senators lineup after he was a healthy scratch in eight of the past 10 games. He replaced rookie forward Curtis Lazar, who was scratched because of an injury.
Predators center Olli Jokinen scored 76 seconds into the third period, his first point of the season, to make it 3-2.
"It’s hard when you give up three goals in one period to come back in this league," Jokinen said. "Every team, they know how to defend. That second period cost us the game."
Laviolette said he liked what he saw from the Predators in the third. The Predators outshot the Senators 16-3 and only some strong work by Lehner kept the Senators ahead.
"There’s a lot of confidence in our room," Laviolette said. "It doesn’t seem like scores matter too much to our group. I think everybody in that room felt like we could win the hockey game. We didn’t tonight, but I was happy that they went out there and played as hard as they did in the third period and fought for a win. It didn’t happen, but that’s a sign of a team that believes that they can do things."