‚ÄčClarke MacArthur knew Dion Phaneuf was on the Senators' radar, but he was he was as surprised as his teammates at the blockbuster trade that brought the former Maple Leafs captain to Ottawa.

The Senators bulked up their blue-line Tuesday by adding Phaneuf in a nine-player trade with archrival Toronto. Senators forward MacArthur said he had been asked about Phaneuf's character in the past, but never imagined anything like this would happen.

"I've been asked in the past what kind of a guy he was and if he's a guy that would fit here and things like that, and obviously he would fit on any team," said MacArthur, who played with Phaneuf for two seasons in Toronto. "Anyone would want him in their top four 'D' and I just answered accordingly.

"I said he's a good guy in the room. I had no idea anything like this was coming or anything like that, but really excited to have him coming in here. But it's upsetting at the same time to lose the guys we have."

Ottawa also added forwards Matt Frattin, Casey Bailey and Ryan Rupert as well as defence prospect Cody Donaghey in exchange for defenceman Jared Cowen, forwards Colin Greening, Milan Michalek and Tobias Lindberg and Ottawa's second-round pick in the 2017 NHL Draft.

Phaneuf has three goals and 24 points through 51 games this season, and has looked more comfortable playing on Toronto's second defensive pairing.

He will look to bolster the blue-line for Ottawa's playoff push. As of Tuesday the Senators (25-23-6) trailed the New York Islanders by four points for the second wild card spot in the Eastern Conference.

"It's obviously a major one for us, we've been looking for someone to help our 'D' corps for a while and he was the option," said Senators captain and all-star defenceman Erik Karlsson.

"Obviously sad to see guys go especially for me to see Milo [Michalek] go, we've been friends since my first year here. We got here at the same time and we've been through a lot, and we're good friends on and off the ice. Unfortunately I've seen a lot of my close friends leave this team now."

Phaneuf to partner with Ceci

Phaneuf is expected to be in the Senators lineup Wednesday night against the Detroit Red Wings.

"This just happened, but right now, I'd say [he'll play with Ceci]," said Senators coach Dave Cameron. "He's going to play lots. He'll probably play with everybody at some point and he's going to play lots."

Cameron doesn't know Phaneuf extremely well, but the two cross paths in the summer as both spend much of the off-season on Prince Edward Island.

"I haven't had much interaction with him," said Cameron. "I've seen him. He spends his summers in Prince Edward Island. I see him there. As a player, I think I know lots about him because when you're in this business you follow and read about, not your own team, but about other teams. I'm really excited to have him."

'I just hope he can bring some of his leadership and his experience and start helping as soon as he plays his first game.' - Senators all-star defenceman Erik Karlsson on newcomer Dion Phaneuf

Defensively the Senators have struggled this season. They've allowed the second most goals in the league (166) and allow an average of 3.07 goals per game. Phaneuf will be expected to solidify Ottawa's second pairing and add a veteran presence to the lineup.

"It's going to be good for our young 'D' corps to get some help," Karlsson said. "I just hope he can bring some of his leadership and his experience and start helping as soon as he plays his first game."

Senators general manager Bryan Murray said he had no qualms making a deal with a division rival.

"From our point of view it's a trade that will give us a little more security on the back end. I hear people talk all the time that we're dreadful in our own end and we haven't been great, we're getting better and we believe this will be a good addition in that process.

"It's about getting an experienced leader, a good person, hard-working, competitive guy to add to the mix in our top four."

The two teams meet for the final time this season March 5 in Toronto.