A bizarre story is emerging from the European Tour, as players at last week’s Open de France are claiming their equipment was tampered with at Le Golf National.

The issue was first raised by Bernd Wiesberger, who took to Facebook on Friday to say his driver’s settings – as well as the big sticks of other players – were changed overnight:

It appears it wasn’t an isolated incident, as Duncan Stewart told the UK’s Bunkered.com he was also a victim of the sabotage.

“I asked one of the Callaway reps to have a look at my driver because it wasn’t going as well as normal,” Stewart said to Bunkered. “He put it back to what should’ve been neutral and the grip was around the wrong way – and it had only been re-gripped two or three weeks ago.

“I’m not one of those that tweaks my driver every week and when I saw Bernd’s tweet, it convinced me more that someone had changed it. The more people you speak to, the more it seems to have been going on.”

Players often leave their clubs at an on-site storage facility during a tournament, making extensive tampering possible. Given the spectrum of adjustability on drivers – along with the fact that not every change is blatantly noticeable – the extent of the sabotage is not known.

The European Tour has not responded to a request for comment.