NICK Kyrgios came to Brisbane last month to spearhead Australia's Davis Cup campaign with a secret in his carry-on baggage.
It emerged on Sunday that Kyrgios has hired Frenchman Sebastien Grosjean to be his part-time coach, with the first tournament they will travel to being this week's Italian Open.
Kyrgios has a first-round clash with Roberto Bautista Agut on Tuesday night (AEST).
Grosjean retweeted a French reporter's inside knowledge that they had first trained together in February.
Kyrgios said when he was at the Davis Cup tie in Brisbane early last month that he was still looking for a coach, having reached a career-high No.13 ranking last year without one.
Grosjean, who reached a world No.4 singles ranking in 2002, does not want to travel on the tour full-time at the moment, making his association with Kyrgios one in which the headstrong Australian will have some space.
Grosjean, 39, coached Frenchman Richard Gasquet from 2014-16, meaning he was in the rival players' box when Kyrgios tanked for a few points in a 2015 Wimbledon loss to Gasquet.
Kyrgios suffered a hip problem during his third-round loss in Madrid to Rafael Nadal last week, and the Italian Open will be a test of the injury with the French Open coming up later this month.
Kyrgios's insistence on touring without a coach has been one of the talking points surrounding his career, with others often making it a bigger issue than he does.
His last touring coaching partnership was a short-lived one with Josh Eagle in 2015.
Eagle said earlier this year that the 22-year-old lacked coping skills under pressure on the tour and on some training days didn't bother to practise for even 15 minutes a day.
Kyrgios previously worked with Simon Rea before and after his 2014 Wimbledon breakthrough against Rafael Nadal, with Rea later going on to coach Sam Stosur for a while and take up the job of Tennis New Zealand's high-performance director.
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