The Boston Bruins continued their very busy offseason on Wednesday, the first day of NHL free agency, by adding offense.

The Bruins traded forwards Reilly Smith and Marc Savard to the Florida Panthers for forward Jimmy Hayes, a former Boston College player from Dorchester, Massachusetts. Hayes scored 19 goals in 72 games for Florida last year.

Savard has missed the last four seasons with post-concussion syndrome.

The Bruins then signed free-agent forward Matt Beleskey to a $19 million five-year deal. Beleskey scored 22 goals in 65 games last season for the Ducks.

A blockbuster trade stole the spotlight of the day.

The Pittsburgh Penguins acquired high-scoring winger Phil Kessel from Toronto, and a handful of prominent defenseman found new homes in free agency.

Mike Green signed a multiyear deal with Detroit, Andrej Sekera signed a $33 million, six-year contract with Edmonton, Paul Martin signed a $19.4 million, four-year deal with San Jose and Francois Beauchemin got a three-year deal with Colorado.

Other notable players to sign with teams on a busy opening day of free agency were forward Michael Frolik, who got a $21.5 million, five-year deal from Calgary, forward Blake Comeau, who signed a three-year deal with the Avalanche and forward Daniel Winnik, who signed a two-year contract with Toronto.

A pair of players who helped Chicago win the Stanley Cup left as free agents with Brad Richards signing a one-year deal in Detroit and Antoine Vermette going back to Arizona four months after being traded to the Blackhawks.

But the biggest move was clearly the one that teamed up Kessel with former MVPs Sidney Crosby and Evgeni Malkin in Pittsburgh.

The Penguins sent forward prospect Kasperi Kapanen, forward Nick Spaling, defenseman Scott Harrington and a 2016 third-round pick to the Maple Leafs for Kessel, forward Tyler Briggs and defenseman Tim Erixon. Conditional draft picks are also involved.

Kessel has 247 goals and 273 assists in nine seasons between Boston and Toronto, including 25 goals and 36 assists for the Maple Leafs in 2014-15.

Kessel’s presence will provide Crosby and Malkin with a capable scorer still in his prime. Injuries devastated Pittsburgh’s depth last season. The Penguins struggled to score goals for long stretches and fell to the New York Rangers in five games in the opening round of the playoffs.

With fewer top players hitting the market as unrestricted free agents, the busiest action was on the blue line, where a handful of teams made some big upgrades.

Green gives the Red Wings a quarterback for their power play after posting 10 goals, 35 assists and 17 power-play points last season with Washington.

Richards, who had 12 goals and 25 assists for Stanley Cup champion Chicago last season, also gives the Red Wings another scoring threat.

The Oilers and Sharks both filled voids on defense with their deals with Sekera and Martin. Sekera had three goals and 20 assists over 73 games with Carolina and Los Angeles last season.

Martin’s signing with San Jose comes a day after the Sharks acquired Martin Jones to be their starting goaltender as GM Doug Wilson has made a strong play to fix a leaky defense that led to the franchise missing the playoffs for the first time since 2003.

Despite losing Richards and Brandon Saad, the Blackhawks were able to lock up one of the players they got in the seven-player deal that sent Saad to Columbus on Tuesday.

Forward Artem Anisimov agreed to a $22.75 million, five-year contract extension with Chicago. The 27-year-old Anisimov had seven goals and 20 assists in 52 games for the Blue Jackets last season. The contract extension begins with the 2016-17 season.

Among the busier teams was the Nashville Predators, who re-signed forward Mike Ribeiro to a two-year, $7 million contract, signed free agent defenseman Barret Jackman and forward Cody Hodgson and acquired forward Max Reinhart in a trade with Calgary for a conditional fourth-round draft pick.

In other news, Carolina officially bought out forward Alexander Semin’s contract. The Hurricanes owe Semin $14 million over the next six years and he is now a free agent.

Vancouver also traded forward Zack Kassian and a 2016 fifth-round pick to Montreal for forward Brandon Prust.

After a busy weekend of goalie movement at the draft, a handful of backups got deals. The Kings signed Jhonas Enroth to a $1.25 million, one-year deal, Philadelphia signed Michal Neuvirth to a multiyear deal and Thomas Greiss got a two-year contract from the Islanders.

Calgary also kept Kari Ramo with a $3.8 million, one-year contract.

RANGERS: Glen Sather stepped down as general manager and was replaced by longtime assistant Jeff Gorton.

Sather remains as team president.

Sather, 71, has been in charge of the Rangers since 2000. The team has made the Eastern Conference finals in three of the past four seasons.