Former Yugoslavia captain Velimir Zajec signed a two year contract on Tuesday to coach Croatian champions Dinamo Zagreb in what will be his second spell in charge of them. The 54-year-old - who had an unsuccessful spell in charge of Dinamo in 1998/99 - replaces Krunoslav Jurcic, who resigned from his post last week despite delivering two league titles and the cup in little over a year at the club. However, Zajec - a former midfielder and winner of 40 caps for the former Yugoslavia - said that he would improve the team's level of performance which had been criticised in the latter part of the season by the club's board. 'This team has its potential. Its latest performances have not been equal to the level of its quality,' said Zajec, who also had a short spell coaching English side Portsmouth (2004/05). 'I will demand from the players that they are more aggressive and play with better quality. 'I have been away for a long time, but I have learnt a lot in Panathinaikos and in England ... and I am more prepared now than I was the last time,' added Zajec, who began his career as a player at Dinamo in 1974 before playing for Greek side Panathinaikos. Dinamo Zagreb's title this season was their fifth successive league crown, taking their total to 12 since Croatia proclaimed independence in 1991. 