County announced the capture of the 21-year-old yesterday morning. Zadkovic, who has represented his country at under-20 and under-23 level, will join the club in the summer.

With the Rams already relegated, manager Paul Jewell is wasting little time in planning for next season.

Jewell has revealed that he also has a deal in place for a second new arrival at Pride Park.

Derby player Tyrone Mears anticipates a overhaul of Derby's squad at the end of the season, and the defender is acutely aware that the four matches remaining this campaign is not a lot of time to cement a place in the manager's plans.

Ahead of tomorrow's trip to West Ham, he said: "It is really important that we go down there and try and lift ourselves after being beaten 6-0 at home by Aston Villa.

"We must try and get something out of the game and try and get something out of the season to take into next season.

"At the end of the day, players here are playing for their future whether it is at Derby or somewhere else.

"I am sure there is going to be a lot of changes. The manager is going to want to bring in his own players - he has already started - and it is up to the players already here to try and fight for their places, or prove to other clubs that they are good enough to step into their side.

"There is a lot to play for and that is why I can't understand that results are not going for us at the minute."

The former West Ham right-back is looking forward to his first return to the club since leaving to join the Rams in January 2007.

Mears feels he has a point to prove after a string of injuries meant the Hammers did not see the best of him during his time at Upton Park.

"It is my old club and of course I want to go back and try to put in a good performance because I don't think I showed what I was capable of," said Mears.

"The injuries made it hard to get a run in the side. It would be good to get a result against my old team."