P1010949USA in trouble vs. Serbia, Djokovic chopped down Isner in three and now Troicki is up in the third set vs. Querrey. Sam was making far too many errors but found his consistency in the fourth set to force a fifth.A couple of observations - the Serbians seem more united on the bench and are giving Troicki superior support and fist pumps. They seem to want it more. Isner and coach Jay Berger are on the US bench but where are the Bryan Brothers? The USA bench seems half full, two kids (hitting partners) seem to be there hanging out. I don't like the vibe on the USA bench compared to Serbia's. The TV cameras show a lot of Djokovic and Courier and the Serbian captain but none of Isner though I think I saw him more up toward the service line. Boise crowd is really into this though and they are lifting Sam. USA desperately needs Sam to win and level the tie at one. Think I spotted Wayne Bryan and Andy Roddick's mom in the crowd.