After his retirement from professional football as a player, he spent several seasons playing futsal, even winning two international caps for Croatia in the sport, and also started his managerial career with Hajduk Split in 2007.

In the summer of 1998, Jarni initially moved to English side Coventry City, signing for £2.6 million from Real Betis.

However, when Real Madrid decided they wanted the player, they successfully bought him from Coventry for £3.4 million, with Jarni having made no appearances whatsoever.

[1] At Real Madrid, Jarni struggled to get his place in the starting line-up and often found himself receiving little playing time as a substitute, although he did manage to finish the season with a total of 27 Primera División appearances on his tally.

One of the highlights of his spell with Real Madrid came 10 days earlier in their third UEFA Champions League group match that season, when he netted a brace in their 6–1 win at home to Sturm Graz.

He was part of the Yugoslav squad that won the 1987 FIFA World Youth Championship in Chile, alongside his future Croatia team-mates Davor Šuker, Zvonimir Boban, Robert Prosinečki and Igor Štimac.

He quickly established himself as a regular with the team and was also part of the Croatian squad for the country's first appearance in the finals of a major tournament, at the UEFA Euro 1996 in England.

Two years later, Jarni was named in the Croatian squad for the country's first World Cup appearance, at the 1998 finals in France, and was an important member of the team that went on to win the bronze medals at the tournament.

One of those assists came later during 1998 World Cup, when he set up Robert Prosinečki's opening goal in Croatia's 2–1 win against the Netherlands in the third-place match.

Jarni started his managerial career in professional football as assistant manager to Sergije Krešić at Hajduk Split in late August 2007.

After Krešić's resignation on 26 October 2007, Jarni was appointed head coach at the club and was initially presented as caretaker manager until the end of the first part of the Croatian league season in December.

[4] The season proved to be a disappointment for Hajduk as they only managed to finish 5th in the league, 30 points behind the champions and archrivals Dinamo Zagreb.

On 4 August 2010, Jarni was appointed new manager at Istra 1961, where he replaced Ante Miše, who had been sacked after the club lost their first two matches of the 2010–11 season in the Croatian first division.

[7] where Jarni lost just 1 game after taking over as the head coach and reached the 4th position in the table but on 9 April, toward the end of the 2013–2014 season, he was asked to leave following internal tension of the club's inability to win the league.

[8] FK Sarajevo finished 3rd in the league this season just trailing with 1 point behind Široki Brijeg and were also winners of the Bosnia Football Cup.