The United States battled to a 2-0 win over El Salvador last night in reach the Gold Cup semi-final.Goals in the first half from Omar Gonzalez and Eric Lichaj handed Bruce Arena’s side the win.But the US had to deal with more than just an El Salvador side eager to win. They had to cope with Henry Romero, who was pulling every dirty trick to distract Jozy Altidore.Midway through the incident, the El Salvador player appeared to twist Altidore’s nipple before a set piece was taken.Moments later, Romero then went all Luis Suarez on Toronto FC’s Altidore, seemingly biting him on the shoulder.Altidore delivered the best response after the match. But first, the nipple twist.

Watch: Romero twists Altidore's nipple

Watch: Then bites his shoulder

It prompted Altidore to gently knock Romero the ground. Romero clearly thought he could force a retaliation out of the former Sunderland striker, so he tried to bite his shoulder minutes later.

Altidore's response was brilliant

The United States’ players saw the funny side of the two incidents.

According to Washington Post reporter Steven Goff, Altidore said: “My girl is mad at me. She’s mad at me, she’s mad at Romero. She’s like ‘Only I can bite you, only I can grab your nipples’.”

Former Everton goalkeeper Tim Howard said, per ESPN’s Jeff Carlisle: “You can’t go around biting people. That’s crazy. [Nipple twisting], that should be allowed, but the biting, no good."

Arena wasn't pleased with his side's performance

Despite the quarter-final victory, Arena lamented his side’s “sloppy” display.

"I thought we had a difficult time tonight," he said, per ESPN. "Our timing wasn't good, we didn't do well with the physicality. The game had no rhythm with all the fouls, and players falling on the ground.

"But we weren't good on top of it. It took us 30 minutes to play a little bit. Then we got a little bit more assertive, and took up good positions on the field, and capitalised on a couple of their mistakes.

"But it was just a sloppy game overall."

Costa Rica next up

The US will now face Costa Rica in Saturday’s semi-final, and Arena is expecting a tough match.

"Certainly they're a good team, we know that," Arena added.

"They beat the U.S. by four goals in November, right? Hopefully we can remember that."

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