They extend into dressing rooms from Los Angeles to New York, from Vancouver to Montreal. They extend to teammates in the NHL who have become rivals in the Olympics only to become teammates once again next week.
Nine NHL teams will have players from both sides in the game Friday, including five players from the St. Louis Blues and four from the Los Angeles Kings, Chicago Blackhawks and Pittsburgh Penguins. The New York Rangers would have four as well, but Derek Stepan is expected to be a healthy scratch for the United States.
"You want those bragging rights," Canada and Kings defenseman Drew Doughty said. "For the rest of the season, for the rest of your life, really.
"I want to beat them so badly."
Doughty said he saw U.S. and Kings goalie Jonathan Quick on Thursday as they were both going to grab a meal in the athlete's village.
"We were talking about hopefully it came down to a shootout, and hopefully I shot," Doughty said.
Canada center Jonathan Toews said he has seen Blackhawks teammate and right wing Patrick Kane of the U.S. around the village, but the two haven't really spoken. What would they possibly say to each other that hasn't been said a hundred times?
"I don't think either of us doubted it at all that at some point we'd be facing off, whether it's the semifinal or the final," Toews said. "To win a gold medal we felt like it's pretty much necessary to go through the U.S. at some point and them the other way around."
Familiarity will likely breed contempt Friday. Redemption will be on the minds of the Americans.
Thirteen players from the U.S. played in Vancouver four years ago when Sidney Crosby broke their hearts with his golden goal in overtime. Even U.S. coach Dan Bylsma, who was in a Pittsburgh restaurant as his star player from the Penguins put the dagger past Ryan Miller, feels the intensity of the rivalry and the revenge at stake -- and he has never coached or played in a Canada-U.S. game.
"I felt the same disappointment as everybody else in that bar," Bylsma said. "But I kind of had a feeling that once he got to the dot it might find the back of the net, which it did. I can't say I was happy for Sid. If it had to be someone I'm not surprised it was Sid. There was a lot of disappointment. I don't know. At the time I wasn't anywhere close to the 2014 Games, but I might have been in a bar in Pittsburgh, I got up from that chair and was ready to try to get to 2014, I know that."
Well, here you go, coach.
The gold medal might not be on the line when the Americans and Canadians face off Friday, but the chance to play for it is just as big right now.
Here are the three keys each team has to follow if it wants that opportunity:
1. Stick with the same lines, get some goals
This appears to be Canada coach Mike Babcock's plan, except for the necessary change on the fourth line because of John Tavares' injury.
Matt Duchene will be in the lineup and playing at his natural canter position between Patrick Sharp and Rick Nash. The other three lines Babcock used in practice Thursday were the same ones he rolled in the game Wednesday. If he sticks with them it will be the first time Canada won't make any drastic line changes after a game in this tournament.
The lines were and should be: Chris Kunitz - Crosby - Patrice Bergeron; Jamie Benn - Ryan Getzlaf - Corey Perry; Patrick Marleau - Jonathan Toews - Jeff Carter; Sharp - Duchene - Nash. Martin St. Louis is the 13th forward.
"That can add a little bit of comfort going into the next game if you're playing with the same guys and you kind of get that rhythm together. But you and I both know that can change with the drop of the puck," Getzlaf said. "You've just got to be prepared for everything and be prepared to go out and work that system no matter who you're playing with."
Babcock admitted after the preliminary-round overtime win against Finland on Sunday that maybe the Canadians were doing too much tinkering with the line combinations. He said Thursday that the plan all along was to have Jamie Benn playing with Perry and Getzlaf, but it took until the fourth game to make it happen. He offered no explanation for it other than this:
"When you have a whole group of people, including management, that have different opinions, sometimes things are different. Is it different than running your own team? Absolutely. It's fun."
Judging from that comment, it's possible that Canada has had too many cooks in the kitchen so far in this tournament, what with four NHL coaches on the staff plus a former NHL coach, and four general managers making up the executive staff.
But it appears they have finally found the lines they like. The next task is to get some goals.
Canada has survived to reach the semifinals despite getting only six goals in four games from its forwards, including three in a span of 12 minutes from Jeff Carter against Austria. Shea Weber and Drew Doughty have combined for seven goals.
The Canadians had 57 shots on goal against Latvia on Wednesday, including 38 from their forwards, but it was a goal from Weber 13:06 into the third period that was the difference in the game.
"Put it in the net. Put it in the net," Babcock said when asked what tweaks can be made following the Latvia game. "We only got impatient a couple times in the game where we gave up chances. We don't give up much; I think we've given up three goals in the tournament if I'm not mistaken. Let's just keep plugging away and doing what we're doing."
2. Get ready for an aggressive forecheck
Canada has not faced an aggressive forecheck yet in the tournament. It will on Friday, and how the Canadians respond will be telling.
They have played four games against teams that have sat back in the neutral zone, spread four skaters across the zone, and dared them to try to attack through the middle.
The Americans want to play fast and they want to forecheck, meaning Canada won't have the same amount of time and space it had against Norway, Austria, Finland and Latvia. However, this shouldn't be a problem for the Canadian players, who are used to being pressured. A bit of familiarity could lead to some instinctual play on the big ice.
"A team like [the U.S.] is going to forecheck, and they're going to skate," Getzlaf said. "It's all about puck possession [Friday] and taking care of the puck at the lines."
3. Don't be afraid to pack the house in front of Carey Price
The Canadians haven't given up too many scoring chances in the tournament, but the odd ones they have yielded have been of the Grade A variety because they've gotten caught trying to push through the clogged neutral zone.
Now that they'll be facing the Americans, a team that also wants to push through the neutral zone with speed, it wouldn't be bad if Canada adopted a defensive system to thwart the U.S. attack.
After all, Canada is skilled enough to create offensive chances off its defense, so why not try to frustrate the Americans, at least early in the game, by doing what their opponents so far in this tournament have tried to do to them?
"They've been scoring a lot of goals, so we've got to keep our stingy defense up, and I think we're going to get more opportunities than we've been getting," Duchene said. "There is so much skill on this team, I know it's only a matter of time before the dam bursts and we start scoring a lot of goals."
1. Paging Patrick Kane, Mr. Kane …
Call it nitpicking if you want, but Patrick Kane has not been as electric as he can be in this tournament, not even close. He is, however, the type of player that can carry his team when he turns it on.
Throughout his career, Kane has been a big-game, big-moment player. He'll need to be that once again Friday.
"I'll just keep trying to do the right things," Kane said. "Hopefully it comes [Friday]. That would be a good time."
The U.S. has scored with relative ease in the tournament (19 goals in four games) despite not getting a single goal from Kane, who has four assists. He hasn't necessarily been bad, but he hasn't been as effective as he could be and needs to be for the Americans to win gold here.
Kane, though, has been through this before, only to come out the other side looking great.
He had a stretch of seven straight games without a goal in the Stanley Cup Playoffs last season. He was frustrated then just like he is now because the problem wasn't the lack of production, it was the lack of chances. He spent time watching video with his dad and decided he was passing up on too many opportunities to shoot the puck.
So Kane entered Game 4 of the Western Conference Final against the Kings with a shoot-first mentality. He had a goal on seven shots in the Blackhawks' 3-2 win in Game 4 of the Western Conference Final against the Kings. Two nights later at United Center, he completed his hat trick in double-overtime to put Chicago into the Stanley Cup Final.
He then scored three goals in the six-game Stanley Cup Final against the Boston Bruins, including two in Game 5, one of which was the winner.
"You're always looking to do more when it's not going into the net, but [I'm] just trying to get the shots through, get them on net and see what happens," Kane said.
2. Ride the shutdown pairs
Ryan Suter might play 30 or more minutes against Canada on Friday. In fact, if the game is close throughout it would be surprising if Suter's minutes don't climb north of that. He played 29:56 against Russia.
Bylsma has the last-change advantage as the home team and he absolutely should use it to get Suter and his defense partner, Ryan McDonagh, on the ice as much as he can.
He called Suter the best player on the ice following the 5-2 quarterfinal win against the Czechs.
"He was absolutely great in the game defensively first and foremost," Bylsma said. "He dealt with their speed, dealt with their skill, dealt with their size. He was great defensively and moved the puck forward, and in the offensive zone he was equally as good. This was easily his best game of the tournament to this point in time and came up absolutely huge for us."
Suter and McDonagh, who has impressed the coaches with his skating and his smarts despite playing on his off side, should see plenty of Crosby's line and a lot of Getzlaf's line too. Those are two completely different lines, so the challenge becomes that much greater. Crosby's line is built to attack with speed and grit; Getzlaf's line is built to attack with brute force.
Brooks Orpik and Paul Martin make up the Americans' second shutdown pair. Beyond that, the depth of the U.S. defense, while it has been impressive so far in the tournament, doesn't match up against the depth of Canada's forwards.
That's why Suter likely will play half the game.
3. Make sure Backes finds Crosby
Once again, the last-change advantage should come into play as Bylsma tries to match forwards against the lines featuring Crosby, Bergeron and Kunitz as well as Getzlaf, Benn and Perry.
We're not including Canada's third and fourth lines in this equation because the Americans will likely have to go straight up against those. They have the ability to do it, especially with two of the NHL's best defensive forwards centering their top two lines in Joe Pavelski and Ryan Kesler.
However, Backes' line, including wings Ryan Callahan and Dustin Brown, is playing with so much abrasiveness in the tournament. Moreover, they're finding the back of the net.
Backes scored and assisted on Brown's goal in the win over the Czechs and the line has combined for five goals and three assists. The International Ice Hockey Federation doesn't keep blocked shots as an individual statistic, but Callahan has thrown himself into a lot of howitzers, especially from the Russian tandem of Alex Ovechkin and Ilya Kovalchuk.
Bylsma hinted he would try to get Backes' line on the ice against Crosby when he met with the media Thursday, but he threw in a caveat.
"Going into games in the NHL, you can look at a matchup of a top line, a Crosby line versus a Backes line," he said. "But in this game, with the depth of the Canadians from top to bottom on their four lines, I don't think you can go straight matchup, one guy against one guy.
"We're certainly going to have David Backes out there in key situations, and some of those will be against Sidney Crosby."
The more the better, because Crosby, as the Americans know, is the most feared offensive forward on Canada's roster, even if he doesn't have a goal in the tournament. He only scored one goal going into the gold-medal game four years ago, but his overtime winner is all that anybody remembers on both sides of the 49th parallel.
Dan Rosen, NHL.com Senior Writer