USA manager Juergen Klinsmann admits he is worried about the appointment of Mexican referee Marco Antonio Rodriguez for Friday's World Cup qualifier.
The US meet Costa Rica in San Jose in CONCACAF qualifying and Klinsmann feels Rodriguez presence for the match - which comes four days before they meet Mexico - is slightly off-putting.
"I don't doubt that Marco Antonio Rodriguez is a great referee," Klinsmann told ESPN Radio Fórmula.
"But at the same time there is something I can't get out of my head. I have eight players with a yellow card and four days later we face Mexico. Truthfully, I don't like this."
The US have Jozy Altidore, Matt Besler, Michael Bradley, Geoff Cameron, Clint Dempsey, Tim Howard, Fabian Johnson and Jermaine Jones all on yellow cards as they strive to seal their advancement to the 20142 World Cup in Brazil.
