RIO DE JANEIRO (AP) — John Speraw ran along the sideline about as close as he could to actually being in the action, cheering Aaron Russell to make a save while crashing into the barrier some 20 feet behind the end line.

"I was willing him to get that ball," the U.S. coach said. "I'm into it. It's the Olympic Games."

Russell didn't quite get there. Moments later, Micah Christenson pulled off a nearly identical play and kept the point going.

It has taken that kind of hustle — not to mention several heart-to-hearts — for the semifinals-bound U.S. men's volleyball team to put itself in position for an Olympic medal.

"It gives me goosebumps talking about it and thinking about it because those are the plays that we're all making for each other," said Christenson, one of eight U.S. first-time Olympians. "We're sacrificing everything we have for each other and we can really see that, it's really evident in our play. And I don't think that's ever going to stop. Those are kind of defining moments in our tournament that really help us."

The fifth-ranked Americans topped second-ranked Poland 25-23, 25-22 25-20 on Wednesday, building serious momentum at Maracanazinho arena after dropping their initial two matches to Canada and Italy before stunning Brazil and finishing off France.

The U.S. next plays Friday against Italy, which beat Olympic first-timer Iran in straight sets. That included a 31-29 first set that finally ended on Italy captain Emanuele Birarelli's block. The Italians beat the U.S. in four sets during pool play — and the Americans haven't lost since.

"We started this tournament horribly, not how we wanted to play," U.S. outside hitter Taylor Sander said. "We really learned from those two matches. Now, we're playing every match like it's a gold-medal match."

Sitting in his hotel room a week ago, Speraw had his doubts after the 0-2 start. Then, the jitters subsided, the volleyball got far better after those team chats, and everything clicked for his young group.

"I had a hunch that if this team — as young as they are and as inexperienced as they are, without tons of adversity — if we were going to reach our very best, it was going to take some adversity within this tournament," Speraw said. "I don't think any of us expected to come into this volleyball match against Poland, as good as they are and as well as they were playing, and come away with a 3-0 win. It's really remarkable. We demonstrated an incredible amount of poise."

From David Lee's leaping blocks and fist-pumping celebrations to high-flying kills by Sander all afternoon and steady setter Christenson leading the offense, the U.S. now has a true shot at the podium. Four years ago in London, the veterans of this group were on the other end of a quarterfinal sweep at the hands of Italy.

Speraw is typically subdued. This time, he let loose on the sideline, yelling and raising his arms in triumph.

"He wants this as bad as we do, if not more," Christenson said. "He's a very level-headed guy, but he also has the yearning to win so much."

Speraw embraced a youth movement for this four-year Olympic cycle. He's proud of the progress made in a matter of 10 days.

"We're competing really hard, and that's all I can ask of these guys," Speraw said. "Guys are playing with incredible fight and energy. I'm beyond ecstatic we're in the position to play for a medal in Rio."