Novak Djokovic's most successful spell as a tennis player came under the guidance of Croatian former tennis player Goran Ivanisevic. The former World No. 2 and winner of the 2001 Wimbledon Championships first worked together sometime in 2018, as Novak Djokovic and then-head coach Marian Vajda felt they needed expert help in strengthening his serve. Goran Ivanisevic was one of the best servers in the world during his time.
The pair experienced the greatest success of their careers together, with Ivanisevic's only major coaching success before this being his help in guiding Marin Cilic to the US Open title in 2014. Meanwhile, Novak Djokovic added 12 of his 24 Grand Slams to his cabinet under the Croatian's guidance.
However, despite the duo's staggering success, they parted ways in March 2024 to everyone's shock. Since then, both Djokovic and Ivanisevic have gone through relatively unsuccessful spells. Here are three reasons why parting ways with Novak Djokovic was Goran Ivanisevic's worst career move.
Novak Djokovic was Goran Ivanisevic's most successful player in his career

The duo first started working together in 2018. It was back when the Serb and his then-coach, Marian Vajda, were looking to innovate in terms of playing style, and they agreed that strengthening his serve would go a long way in his quest for greatness.
Goran Ivanisevic was approached. The Croatian coach had previously worked with the likes of Marin Cilic, Tomas Berdych, and Milos Raonic before joining hands with the Serb, and had even famously overseen Cilic's spectacular run to the 2014 US Open title.
From 2018 to 2022, Ivanisevic worked in tandem with Marian Vajda as Novak Djokovic's primary coaching team. However, following a split with head coach Vajda in 2022, Goran Ivanisevic stepped into the head coach's shoes.
The Serb's run under Goran Ivanisevic saw him win an astonishing four Australian Opens, two Roland Garros titles, four Wimbledon Championships, and two US Open titles. On top of that, the 24-time Grand Slam winner also won two year-end Tour finals in 2022 and 2023, and cemented his place as the all-time leader in all-time earnings in the Open Era with a whopping $188,934,053 to date.
This was also Goran Ivanisevic's most successful coaching stint with a player, as well as his longest ever, with his three-year partnership with Cilic coming second. The Croatian coach will miss his stint with the Serbian tennis great and rue it as an opportunity that got away.
Since coaching Novak Djokovic, Goran Ivanisevic has had several unsuccessful and brief stints as a coach

Since parting ways with the Serb in March 2024, Goran Ivanisevic has gone on to have multiple stints as a coach with players on the tour that were short-lived and ultimately unsuccessful.
Soon after splitting up with the now 38-year-old Goran Ivanisevic was announced as Elena Rybakina's coach in November of the same year. The 2022 Wimbledon winner's partnership with the 24-time Grand Slam winner's most recent coach sent a statement across the WTA tour, with fans expecting a storm to come.
However, the duo encountered problems outside the court, which led to Ivanisevic stepping back from his role and describing the stint as a "strange and sad story."
The pair parted in January 2025 following Rybakina's fourth-round exit at the Australian Open.
Following an unsuccessful Roland Garros outing, Greek tennis player Stefanos Tsitsipas then announced the Croatian as his coach, hoping to enhance his game going into the grass court season. But, consecutive early exits at the Halle Open and All England Championships saw the duo part ways on July 23.
Tsitsipas described his stint with Ivanisevic as a "brief but intense experience and a truly valuable chapter" in his journey. The pair parted rather controversially as Ivanisevic made public claims surrounding the Greek's fitness.
Ivanisevic's reputation as a coach has taken a hit since parting ways with Novak Djokovic

Since parting ways with the Serb in 2024, Ivanisevic has had brief spells as a coach with no real success. This will weigh in the Croatian's mind, as he was accustomed to the routine highs of winning Grand Slams, and even before that, with Marin Cilic, cementing his status as a title-winning coach.
However, multiple short and controversial exits with Elena Rybakina and Stefanos Tsitsipas have negatively affected his reputation as a coach. Players will now proceed with caution, hoping there is no controversy off the court, and wondering if Ivanisevic will add enough value to give them the extra edge.
There is no doubt that splitting up with Novak Djokovic was Goran Ivanisevic's worst career choice as a coach.
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