Shane Lowry has parted ways with longtime caddie Brian "Bo" Martin, the Irish Independent reported.
The report said the pairing had lost their "spark" and "chemistry" and that last weekend's split was amicable.
Martin was on the bag when Lowry won The Open Championship in 2019 at Royal Portrush in Northern Ireland.
Lowry, 35, of Dublin, and Martin had been together since 2018.
Other notable finishes together included tying for third at the 2022 Masters and tying for fourth at the 2021 PGA Championship.
It has been a frustrating start to 2023 for Lowry. Two weeks ago at the Abu Dhabi HSBC Championship, he entered Sunday with a share of the lead but carded a final-round 76 to finish nine shots off the pace. Last week he missed the cut at the Dubai Desert Classic.