I've seen U.S. Men's National Team foes employ plenty of different tactics to stop the Americans, but El Salvador hit a new low when they utilized some hidden, cheap tricks that should've deserved red cards.

Trailing 2-0 in the second half of a Gold Cup Quarterfinal matchup, El Salvador became desperate. With the results on the field not there, Darwin Ceren and Henry Romero took matters into their own hands...and teeth.

Romero tested out two different dirty tactics, both of which were caught on video.

[embed]https://twitter.com/TroyMachir/status/887863642439294977?ref_src=twsrc%5Etfw&ref_url=http%3A%2F%2Fftw.usatoday.com%2F2017%2F07%2Fusmnt-gold-cup-usa-el-salvador-jozy-altidore-nipple-twist-shoulder-bite-quote-hilarious-video[/embed]

In this first clip, we can clearly see Romero reach for and latch onto Jozy Altidore's nipple, giving it a rough twist in the process. I've seen this tactic utilized between fighting brothers, but never on a soccer field.

[embed]https://twitter.com/cjzero/status/887863893560709124[/embed]

Our second video clip sees the same El Salvador defender, Romero, biting Altidore from behind. Apparently all is fair in love, war and soccer.

Thankfully, after the match ended and the USMNT came away with a 2-0 quarterfinal victory, Altidore could share a laugh about his encounters with Romero.

[embed]https://twitter.com/SoccerInsider/status/887887951346122752?ref_src=twsrc%5Etfw&ref_url=http%3A%2F%2Fftw.usatoday.com%2F2017%2F07%2Fusmnt-gold-cup-usa-el-salvador-jozy-altidore-nipple-twist-shoulder-bite-quote-hilarious-video[/embed]

Unfortunately, El Salvador's mood teetered more towards angry vengeance than laughter. That's when Ceren joined Romero's efforts and took a munch straight out of Omar Gonzalez's back.

[embed]https://www.youtube.com/watch?v=DQqobHfOGfA[/embed]

I'm not sure what possessed El Salvador to go on such a dirty spree in the second half, but it's sad any national team would think these tricks are okay. Frankly, Romero and Ceren are incredibly lucky the referee didn't see all of this nonsense; otherwise, the USMNT would've enjoyed a two-man advantage.

They've either been binge-watching too much of AMC's The Walking Dead or Luis Suarez highlight videos.

[embed]https://www.youtube.com/watch?v=Uy31pdfntUw[/embed]