He is said to have complained about not getting paid for playing, and he also wasn't wearing a USA cap - a rumour that this was as a protest at not getting paid has been denied. However, the European crowd has taken to waving their own headgear in the air, chanting "hats off for your bank account". And then this happened:
Angry Rory McIlroy boils over in Ryder Cup car park row with US caddie
Donald [European captain] explained what angered McIlroy during the celebrations of Joe LaCava, caddie for Patrick Cantlay, at the end of an American fourball win. A finger-jabbing McIlroy was later filmed making his disgust perfectly plain in the car park of Marco Simone Golf Club, where he was bundled into a vehicle by his teammate Shane Lowry.
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Cantlay converted a 43ft putt, with McIlroy still waiting to play. McIlroy and Matt Fitzpatrick missed, meaning victory for Cantlay and Wyndham Clark. “I saw it unfold when Patrick made that putt,” Donald said. “Joe was waving his hat. There was some hat waving going on throughout the day from the crowd. Not [from] our players. I talked to Rory. He politely asked Joe to move aside. He was in his line of vision. He stood there and didn’t move for a while and continued to wave the hat, so Rory was upset about that.”
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“Listen, we’re all competitors,” said Donald. “We all want to win but we want to do it in the right way. From what Rory told me, he did ask Joe to move. He took a long time to move. It was a little off-putting because he still had to putt. So Rory got upset and I understand that.”
Lowry and Justin Rose had also made their displeasure towards LaCava plain. LaCava had fired back verbally. Donald admired the way European players defended McIlroy’s cause. “Of course they have their backs,” said the captain. “We are a big family this week. We support each other.”
https://www.theguardian.com/sport/2023/sep/30/angry-rory-mcilroy-boils-over-in-ryder-cup-car-park-row-with-us-caddie
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