Serbia midfielder Nemanja Matic has admitted that he is considering retiring from international duty because of his teammates' "unacceptable" attitude.
Radovan Curcic's side, who did not qualify for Euro 2016 after finishing fourth in a five-team Group I, were thumped 4-1 in a friendly away to the Czech Republic on Friday night.
"I always try to lead by example but some people don't want to see that," the Chelsea midfielder is quoted as saying by Sky Sports News.
"The attitude of some players is unacceptable, not just on the pitch but off it too, and it was obvious from the moment we got together on Monday. I told our coach there is no point in me carrying on with the national team if things don't change.
"I'd really like to know whether some of my team-mates apply the same poor working ethic at their clubs as they do in the national team most of the time."
The 27-year-old has 26 senior caps for his country, who sit 49th in the FIFA world rankings and won four points from a possible 24 in Euro 2016 qualifying.