Silver medalist Charlotte Kalla of Sweden, gold medalist Marit Bjoergen of Norway and bronze medalist Heidi Weng of Norway celebrate after the women’s skiathlon.  (Clive Mason/Getty Images)

The United States won its first medal, and it was gold. The women’s hockey team kicked off its push for a gold medal of its own. And Norway dominated cross-country skiing, to no one’s surprise.

It’s good, being up at 4 a.m. on a Saturday. Really.

The U.S. men’s snowboard slopestyle team was not expected to do much of anything after Shaun White dropped out earlier in the week. The three Americans had to go through Saturday’s very early morning round of semifinals, then the finals. When it was all over, Sage Kotsenburg had a gold medal, and we had our first Olympic surprise.

If you are not an Olympic purist, it was a good morning to sleep in. The quantity of event coverage before 7 a.m. was not what one would like: slopestyle was available only by streaming; NBC is saving it for prime time, and don’t those programmers look smart now. But the quality this morning was high.

At 3 a.m., the U.S. women’s hockey team opened the Olympics with a 3-1 win over Finland. While the game was not as close as the score indicates, it is still a sign that the gap is narrowing between the Big Two — the United States and Canada — and the rest of the world. In fact, the format of the tournament has been changed to reflect that change. Group A is comprised of the top four teams in the tournament — the United States, Canada, Finland and Switzerland. So the best teams here will duke it out early, and just two will move into the next round. That change puts some early pressure on the Big Two, who used to skate through the round-robin portion of the tournament with ease.

The Americans got ahead, 3-0, after two periods — Alex Carpenter, daughter of former NHL player Bobby Carpenter, scored the third goal — and then just hung on, giving up a power play goal late in the game. The Finnish goalie, Noora Raty, is good — she has signed to play with a Russian team. A Russian men’s team. NBC tells us that one of her two favorite NHL goalies is the Capitals’ Braden Holtby. Hmmmm.

What you’ll see when you watch women’s hockey is a slower game than the men’s, of course, but you’ll also see better teamwork because these players are not plucked from around the world and brought to an Olympics, thrown on the ice for a few days of practice and then expected to play a fluid game. They have their own pre-Olympic season and it shows. The Americans next play Switzerland on Monday (5 a.m. ET).

Then we switched to another women’s sport, the skiathlon, which is just a new name for the pursuit. That means two laps skied in the classical style — skies parallel, in tracks for parts of the course, and an emphasis on arm strength — and then two laps in freestyle, or what the skiers call “skating,” and it looks a little like speed skating on skis.

There is a swap of skis and poles in the middle of the race. The skiers glide into little “changing areas” of sorts, step out of their classical skis, put on their freestyle skis, pull off one set of poles and put on another set, and off they go. Like a pit stop in a NASCAR race, time is of the essence. Poor Justyna Kowalczyk of Poland fell while turning into her “changing booth” and that might have cost her a medal or at least a better finish.

Cross-country is an original Winter Olympics sport and huge all over Europe. The crowds are large and loud, and there are a lot of fans with Norwegian flags painted on their faces, with good reason. The Norwegians dominate this sport, and that was the case today as they took three of the top four spots. Cross-country skiing is all about the wax, and the Norwegians must have a secret family recipe. Sweden’s Charlotta Kalla took the silver.

Cross-country legend Bjorn Daehlie, who is now in the ski clothing business (you’ll see his logo a lot during the next two weeks), was watching from the stands. My biggest goal is a BJ U.S. ear warmer. Co-workers, take note.

American Jessica Diggins finished eighth, a terrific performance considering she was in 25th place after the classical portion. Diggins, 22, attributed her climb to being a “stronger skater” and, of course, to the wax on her skis. Cross-country skiers talk about wax the way NASCAR drivers talk about sponsors.

“I heard my parents out there and during the race I was, like, ‘Oh my God, that was my mom!’ ” said Diggins, who sported a pink and blue pony tail, dangly diamond earrings — maybe they weren’t real diamonds, but they still looked nice — and a huge smile. NBC should hope she makes the cut for the team event; the United States does have a medal chance and she’s great on camera.

More Olympic coverage from the Post:

American Sage Kotsenburg wins snowboard slopestyle gold

Mike Wise: Flag-bearer’s Olympic quests

Sally Jenkins: Hotel complaints aren’t the half of it