Hjalmarsson went to Arizona. Chicago got defenseman Connor Murphy and forward Laurent Dauphin in the trade.
Panarin was traded to Columbus Blue Jackets in a trade that brought forward Brandon Saad, a two-time Stanley Cup champion with the Blackhawks, back to Chicago.
[TRADE COVERAGE: Reaves to Penguins | Schenn to Blues | Stepan to Coyotes | Panarin to Blue Jackets]
In the Saad-Panarin trade, Chicago acquired goalie Anton Forsberg and a fifth-round pick in 2018 while also giving up forward Tyler Motte and their sixth-round pick (No. 170) this year. Forsberg will likely be the backup to Corey Crawford next season.
The Coyotes added center Derek Stepan and goalie Antti Raanta in a trade with the New York Rangers, giving up 21-year-old defenseman Anthony DeAngelo and the No. 7 pick in this year's draft. The Rangers used the pick to select Swedish forward Lias Andersson.
In another trade of note, the Philadelphia Flyers sent forward Brayden Schenn to the St. Louis Blues for center Jori Lehtera, the No. 27 pick, which they used on center Morgan Frost from Saulte Ste. Marie of the Ontario Hockey League, and a conditional first-round pick next year.
Now that the dust has settled, let's break it all down:
Why did Chicago trade Hjalmarsson?
The Blackhawks like the 6-foot-4 Murphy, 24, a lot. Adding Dauphin, 22, was a clincher.
"Connor is a very impressive young man," Chicago general manager Stan Bowman said. "He has a lot of character, leadership. We really like his size, his physicality, his overall game."
Hjalmarsson was excellent for the Blackhawks, making him difficult to give up. However, he is 30, has played hard minutes in 623 regular-season games and another 128 in the Stanley Cup Playoffs, and has blocked 1,155 shots since the 2009-10 season. Only five other players have blocked as many in that span.
The thinking is that Hjalmarsson, who has two years left on his contract with a $4.1 million NHL salary-cap charge, according to CapFriendly.com, will eventually break down. Murphy has fresh legs and five years left on his contract with a $3.85 million cap charge. His game has a chance to blossom.
Video: Trade Recaps in the NHL Draft
Why did Arizona want Hjalmarsson?
Arizona defenseman Oliver Ekman-Larsson struggled last season, but the feeling is he can shine with Hjalmarsson, who is a familiar defense partner; they have played for Sweden in international tournaments, including the World Cup of Hockey 2016.
"Hjalmarsson is an elite defender, one of the best, and he kind of covers up and frees Oliver up to do his thing," Arizona GM John Chayka said. "Obviously, they are good friends and I think there is a lot of synergy there."
Why did the Blackhawks prefer Saad to Panarin?
Saad and Panarin each has a $6 million cap charge, but Saad has four years remaining on his contract and Panarin has two left on his. The Blackhawks wanted the cost certainty.
Chicago also needed a player who could help make up for the absence of Marian Hossa, who will miss the 2017-18 season because of a skin disorder. Saad can do that with his skating and two-way game.
The Blackhawks feel that Panarin's role can eventually be filled by Alex Debrincat, a dynamic 5-foot-7 forward who led the OHL and set an Erie record with 65 goals in 63 games this season. He added 62 assists.
The big plus is that the Blackhawks know Saad well. Expect him to play with Jonathan Toews, but he has also played with Patrick Kane.
Video: The crew discusses the Saad-Panarin trade
Why did Columbus want Panarin instead of Saad?
The Blue Jackets needed a dangerous scorer, a true finisher. Panarin is that.
Columbus felt it was exposed in the playoffs when it struggled to score against the Pittsburgh Penguins in the Eastern Conference First Round. Columbus scored 13 goals on 194 shots (6.7 percent). Pittsburgh scored 21 goals on 171 shots (12.3 percent). The Blue Jackets lost the series in five games.
Columbus GM Jarmo Kekalainen said he feels the Blue Jackets can make up for the loss of Saad with 23-year-old forward Josh Anderson, who scored 17 goals, all at even strength, this season.
Why did Arizona want Stepan and Raanta?
The Coyotes needed a No. 1 center and a No. 1 goalie. They think they got both.
Chayka said Stepan checks all the boxes for him as a two-way center who can play on play on both special-teams units and be a top point producer. He said Raanta, though he's never been a No. 1, was at the top of the list of goalies he wanted to acquire.
"We need winners," Chayka said. "We have a lot of great young players. We need some leaders and some guys to show them how it's done."
Why did the Rangers trade Stepan and Raanta?
They wanted to get into the top 10 of the draft. They also wanted a young, puck-moving, right-handed defenseman and to move Stepan's $6.5 million salary-cap charge.
Arizona insisted on getting Raanta in the trade, and the Rangers were amenable to it because they believe they can get a backup goalie in free agency to play 25-30 games behind Henrik Lundqvist.
The Rangers have about $20 million in cap space. They need to add depth at center, but GM Jeff Gorton and coach Alain Vigneault feel Mika Zibanejad and Kevin Hayes can be the top two centers, which means the Rangers might look for help at the position in free agency.
The Rangers also might be in the market for an experienced right-handed defenseman to play with Ryan McDonagh. They should have the cap space to sign defenseman Kevin Shattenkirk, but it's not clear if they will go that route.
Why did the Blues-Flyers trade happen?
From the Blues' perspective, it was about production.
Schenn has scored at least 25 goals and 55 points in each of the past two seasons. He's a player on the rise. Lehtera's production has declined in each of the past two seasons; he has gone from 44 points in 75 games as a rookie in 2014-15 to 34 points in 79 games in 2015-16 to 22 points in 64 games this season.
Blues general manager Doug Armstrong said he likes that Schenn is 25, which means he fits into the age group of the St. Louis' core players, who include forwards Vladimir Tarasenko (25) and Jaden Schwartz (24), and defensemen Alex Pietrangelo (27) and Colton Parayko (24).
In addition, Schenn is signed for three more seasons with a $5.125 million cap charge. Armstrong said he liked that, especially because that cap charge isn't much bigger than that of Lehtera, who is 29 and has a $4.7 million charge for the next two seasons.
Flyers GM Ron Hextall said the Blues came to them with the offer, that Philadelphia wasn't shopping Schenn. But the Flyers selected center Nolan Patrick with the No. 2 pick Friday, so that likely made trading Schenn to get extra first-round picks more appealing.