The 20-year-old has worked with Christensen since the tender age of six, with the veteran coach helping nurture Rune into one of tennis' brightest prospects. But in the past year, Rune added a new member to his coaching team - renowned French coach and instructor Patrick Mouratoglou.
Mouratoglou jumped onto Rune's treadmill last October after his coaching collaboration with Simona Halep came to a standstill due to the Romanian's provisional suspension from the Tour due to doping charges. Rune has been training at the Mouratoglou Tennis Academy since 2016, and it was no secret he admired the Frenchman's work.
Rune brought Mouratoglou on board to assist right-hand man Christensen, and under his tutelage, the Danish young gun shockingly won his maiden ATP Masters 1000 title at the backend of last year. But their partnership only lasted six months with Rune eventually taking the plunge in ending their alliance.
While the word was that Mouratoglou was no longer part of the coaching team, the ex-coach of Serena Williams was seen in Rune's player box throughout the clay-court season, where Lars Christensen was on a sabbatical.
Mouratoglou continued to work with the Dane in an unofficial capacity, but it looks like it was never the plan according to Rune's mother. Speaking to Danish tabloid newspaper Ekstra Bladet, Aneke revealed massive issues behind the scenes between the two coaches.
"I don't know what will happen with the coaching situation now. It's a bit strange. The team that worked at the end of the year (2022) suddenly didn't work in Australia. There were ego clashes between the coaches. The team that worked in the gravel season suddenly doesn't work now. Ego clash again? I don't know."
Aneke adds of Rune's recent exit at the US Open, that the coaches' differing opinions have come at the expense of his son's recent wayward results. She advises her son to go back to the drawing board and stick to what worked before, which is to retain the services of Christensen only.
"The fact is that it is Holger who pays the price for it every time, and that cannot be right. It is Holger himself who sets his team. But there should be no doubt that the team we have always had has always achieved our objectives."
" I would encourage Holger and Lars to get back into work clothes together when he has finished helping Clara Tauson in the US Open."