The Toronto Maple Leafs’ rebuild started in earnest Sunday.

Impending unrestricted free agents Cody Franson and Mike Santorelli were dealt to Nashville for the Predators’ first-round pick in June, prospect Brendan Leipsic and veteran forward Olli Jokinen.

"We feel that the pieces we got are good, they're quality pieces," general manager Dave Nonis said on a conference call Sunday. "We just felt it was the right time to act on it.

"You're talking about two players who were going to be unrestricted. We felt that we couldn't risk not getting something for them in the event that we couldn't re-sign them. It was important that we got some assets back."

Franson, a 27-year-old right-handed defenceman, leaves Toronto after three-plus seasons. He had six goals and 32 points in 55 games this season for the Leafs.

In a statement released by the Predators, GM David Poile said it was a team goal to add a veteran defenceman before the March 2 NHL trade deadline "who could play in all situations.

"Cody brings size, offensive ability and the capacity to play in all situations to our lineup," said the veteran GM. "He is the perfect component to round out our defensive corps and give us eight proven NHL defencemen."

One of Franson's more important goals with the Leafs was his second of the contest in Game 7 of the 2013 Eastern Conference quarter-finals against Boston.

Poile talked about how Franson and Santorelli began their NHL careers in Nashville. Franson, a third-round draft pick of the Predators in 2005, played two seasons there, starting in the 2009-10 season. Santorelli made his NHL debut the following campaign with Nashville. The Predators drafted the Vancouver native in the sixth round in 2004.

"They know our organization and still have former teammates and friends on the roster," Poile said. "We are fully confident that they will seamlessly fit into our team.

"We were fortunate to do this … with players who are in the prime of their careers more than two weeks before the [trade] deadline in order to give them more time to contribute and gel with their [new] teammates."

Franson was never able to strike a long-term agreement with Toronto, agreeing to three one-year contracts after the Leafs acquired him in a July 3, 2011 trade with Nashville along with forward Matthew Lombardi for Robert Slaney, Brett Lebda and a fourth-round pick.

Franson increased his point totals in each of his first three seasons with the Maple Leafs and is two points shy of surpassing his career high of 33 from last season.

Blue-liners with Franson’s size (six-foot-five, 213 pounds), offensive capability and right-handed shot are always attractive, especially for a playoff-bound team like Nashville.

'I think my game's kind of taken a step forward since last year. ... I just want to keep getting better.' - Former Maple Leafs centre Mike Santorelli

The Predators, who failed to gain a playoff berth in each of the past two seasons, entered play Sunday with the best record in the NHL at 38-12-6 and riding a five-game win streak. Toronto, on the other hand, is 14th in the 16-team Eastern Conference with a 23-29-5 mark.

Santorelli, 29, was a free-agent signing by Toronto last off-season and impressed from the start with his strong work ethic.

"Honestly I think my game's kind of taken a step forward since last year," Santorelli, who compiled 28 points in 49 games with Vancouver, said last week. "Last year was definitely a big bounce-back year for me. I think I've carried it over and gotten better. That's the mind-set. I just want to keep getting better."

The seventh-year NHL centre had 11 goals and 29 points in 57 games with the Leafs. His most productive season was 2010-11 with Florida when he collected 20 goals and 41 points in his only full 82-game season.

"Mike is a versatile player that can move up and down the lineup based on the situation and an excellent complement to our existing group of forwards," said Poile. "He has fantastic speed, is excellent in the faceoff circle, and can play all three forward positions if called upon."

Leipsic, 20, is a five-foot-nine, 165-pound left-winger from Winnipeg who played 47 games with Nashville's American Hockey League affiliate in Milwaukee, amassing 35 points on seven goals and 28 assists. In the 2012-13 season, his 120 points led the Canadian Hockey League. Leipsic will report to the AHL's Toronto Marlies.

"He's a gifted young man that's going to take some time," Nonis said. "We've got time with him. … We'll try to bring him along slowly, but we like his upside in terms of his offensive ability and the way he competes."

The 36-year-old Jokinen won’t be part of the Maple Leafs' rebuild, having scored just three goals and six points in 48 contests this season. The Finnish forward has 320 goals and 746 points in 1,217 NHL games.

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With files from The Canadian Press