Griekspoor and Vliegen had been together since 2014, when Griekspoor was a youth player. After ten years together, the pair parted ways in October 2024, stating they "had grown too close together" and Griekspoor needed a new impulse in his career.
The 28-year-old Griekspoor hired Dennis Sporrel as his coach in February before adding former pro Xavier Melisse to his team shortly after. Griekspoor let Melisse go soon after and called the short-lived collaboration "very disappointing."
After Griekspoor also let Sporrel walk, the highest-ranked Dutch tennis player held several talks with foreign coaches, including Swedish Mikael Tillstrom, who told Griekspoor he'd rather stay with Gael Monfils. Scott Griekspoor, Tallon's brother, and fitness coach Sebastian Pisano took on the coach role after Sporrel's dismissal.
Vliegen, with whom Griekspoor claimed his only two tournament wins in Rosmalen and Pune, has rejoined Griekspoor's team effective immediately and will be by Griekspoor's side this week as the Dutchman returns from injury at the ATP 250 tournament in Mallorca.