Queens Park Rangers won the play-off final against Derby County 1:0 and secured promotion to Premiership next season, and Niko Kranjčar, who started in the QPR first team, needed to be substituted in the 33rd minute.
Kranjčar had a hamstring problem, received immediate treatment, and contacted Croatian national team's medical staff.
On Monday, he is to undergo MR tests. Only afterwards will his status regarding Croatia's World Cup preparations be known. At this moment, it is too early to predict anything.
