|Rugby World Cup|
|Hosts: England Dates: 18 September-31 October|
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A surprise visit from Usain Bolt has boosted Ireland's self-belief for the Rugby World Cup, says hooker Rory Best.
Six-time Olympic gold medallist Bolt had dinner with the squad in London before their 21-13 loss to England in a warm-up match last week.
Ireland start their World Cup campaign against Canada on Saturday, 17 days after Bolt won the third of his three gold medals at the World Championships.
"To meet someone like that was unbelievable," said 85-cap Best.
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The 33-year-old said Ireland's players listened intently to Bolt's explanation of how he turned around his season by beating Justin Gatlin in both individual sprints in Beijing.
Joe Schmidt's side are preparing to open their Pool D campaign this weekend after back-to-back defeats by Wales and England.
"It was great just to get his thoughts on things," added Best.
"The big thing, from our point of view, was that he says when he goes into championships and he feels good, he knows he's going to perform.
"It's not necessarily about how events leading into it have gone. It is about how he's feeling himself.
"From our point of view, we're feeling pretty good at the minute. But, obviously, the results over the last two games haven't gone the way we wanted.
"He has a lot of self-belief. He knows when he prepares well and is ready, he can perform."
Best joked that Bolt even appeared to tower over 6ft 6in Ireland talisman Paul O'Connell when he met the squad.
"The big thing that struck me about him, as a presence, was just how big he is," he said.
"Paulie went to present him with a shirt. Paulie still claims he had an inch on him, but I'm not convinced."