The U.S. has its biggest World Cup win in a generation. Now it must do it all again without its star forward.

SANTA CLARA, Calif. — Blood pooled near Malik Tillman’s toes as he stood over a free kick Wednesday evening.

The U.S. midfielder’s boot had been stepped on and split open during the World Cup’s round of 32 match against Bosnia-Herzegovina. The puncture left a hole in his sock between his big and middle toes, where a red stain formed.

But the 82nd minute of a knockout game, with the U.S. clinging to a 1-0 lead and down to 10 men after a controversial red card sent off scoring star Folarin Balogun, was not the time for Tillman to focus on the pain.

“I’ve been dreaming about this game,” Tillman said. “I’ve been dreaming about maybe taking a free kick and scoring a free kick.”

Surveying a wall of Bosnian players the height of NBA forwards, he and teammate Antonee Robinson discussed aiming the ball around the wall or under it. With a strike of his pained right foot, Tillman ultimately curved a high-arching shot over the heads of Bosnia’s defenders toward the goal’s near post, where it found the back of the net after deflecting off the goalkeeper’s glove.

A packed stadium here in California, awash in stars-and-stripes jerseys, erupted in relief.

Tillman’s goal gave the U.S. the breathing room it needed to close out a 2-0 win that stands as its most important in a generation.

Not since 2002 had the U.S. men won a game in the knockout round at a World Cup. To break that streak, the U.S. had to survive a whiplash of emotions and hold together to secure a matchup against Belgium in the round of 16 on Monday.

“We were talking in the cooling break,” U.S. coach Mauricio Pochettino said. “That was the moment to show to everyone, to show ourself that it’s not only empty words when we say we are a family.”

Now, to keep its run alive in the World Cup, the U.S. will have to replicate its performance again in the round of 16, and win while missing its top goal-scorer.

It was Balogun who finally broke the scoreless deadlock with a goal in the 45th minute — his third goal of this tournament.

Yet only 19 minutes later, he was sent off after a review by the Video Assistant Referee (VAR).

Balogun’s cleat raked the back of a Bosnian opponent’s calf as both lunged for the ball, leading to a red card that Pochettino strongly disagreed with, saying Balogun never intended to injure his opponent.

Pochettino wanted to appeal the card, until he was told it was not possible within FIFA rules.

“He’s very disappointed,” Pochettino said of his star forward. “He’s sad. But also he’s happy because we qualified.”

The pro-U.S. crowd went quiet, then roared with boos, after the red card because it recognized the decision’s long-reaching damage.

The U.S. was not only down to 10 men for the final 35 minutes Wednesday, but it will also play without Balogun against Belgium because a red card triggers a one-game suspension. Balogun was not made available to speak with reporters after the match, a U.S. spokesman said, citing a FIFA rule.

“We told him that we’ve got his back,” defender Chris Richards said. “We know we’re a team of 26, not just one.”

The emotions of U.S. players, already charged playing on home soil, could have turned against them.

“How they managed the situation,” Pochettino said, “was amazing.”

Perhaps that was because they have done it before.

When a calf injury sidelined Christian Pulisic midway through its first game of the group stage, the U.S. closed out that win, then shutout Australia in its next game as Pulisic stayed out of the lineup.

Pochettino said the U.S. would choose from “different options” to replace Balogun against Belgium. One candidate, Hadji Wright, said he would be ready if called upon.

Balogun reacts after receiving a red card during the second half of the match between United States and Bosnia and Herzegovina on Wednesday. Robert Gauthier / Los Angeles Times via Getty Images

“One-hundred percent confident in the boys,” Wright said. “We’re a gritty team. We know what to do in those situations.”

Said Pulisic, in a post-match interview with FOX: “For us to dig in deep like that and get another goal and to defend like we did, it took a real team effort. We’re proud of that.”

That team effort required the second shutout of the tournament for a defense that was seen as a potential weak link entering the World Cup.

That unit will now plan for a Belgium team that won by coming back from a 2-0 deficit by scoring in the 86th and 89th minutes and then the final moments of extra time. The Red Devils boast well-known — if aging — stars like Kevin De Bruyne, Romelu Lukaku and Leandro Trossard.

A win also took Tillman’s breakout moment.

Raised in Germany, where he now plays professionally, Tillman was asked before the World Cup began to play in a slightly different role in the midfield.

Teammates had praised his effort during the tournament, and Pochettino has called him “an amazing player full of talent,” but his contributions had gone mostly under-the-radar, befitting his reserved personality. Until Wednesday, after his cold-blooded goal.

“I’m a different type of person on the pitch,” Tillman said. “Maybe you don’t really see my emotions, but if you score a goal like this, I think you guys saw my emotions.”

Tillman smiled slyly. More important, he said, was that on Wednesday, the U.S. saw it can win in adverse conditions.

“Of course, we’re going to miss (Balogun),” Tillman said. “But I think we have great players who can replace him.”