Rising Australian tennis star Nick Kyrgios says he's pumped and ready for a first taste of Davis Cup after his surprise selection for the World Group playoff against Poland.
The 18-year-old became the 103rd player selected for the 28-time champion Davis Cup nation after captain Pat Rafter handed him a late call up-for the crunch tie, starting in Warsaw on Friday.
Kyrgios replaces Marinko Matosevic in the four-man squad after impressing Rafter in training over the past fortnight.
While Kyrgios is no guarantee to play a match as Australia bids to return to the competition's top tier for the first time since 2007, his selection represents a huge vote of confidence from Rafter.
At 18 he is not the youngest to be picked for Australia but he's among the most inexperienced, having only just shifted his full focus from juniors to the senior tour.
The former world No.1 junior made a remarkable senior grand slam debut when he upset Czech veteran Radek Stepanek in the first round of the French Open and his Davis Cup selection continues a rapid rise.
"Honoured to be selected for the Australian DavisCup team, I'm told I'm the 103rd player to represent Australia. Pumped and prepared!," Kyrgios wrote on Twitter.
Rafter said earlier this week he had been highly impressed by Kyrgios but indicated it may be too soon to include him.
"I just don't know how his legs are going to hold up over five sets on clay in the brutal Davis Cup environment," Rafter told AAP.
"But talent wise, he's up there. It's fantastic."
With Lleyton Hewitt and Bernard Tomic leading Australia into battle against a Poland side missing injured leading light Jerzy Janowicz, Rafter would ideally be hoping for an early victory - allowing for Kyrgios to make his debut in a dead rubber on Sunday.
Kyrgios' selection comes as a blow to Matosevic, who is still to prove himself under pressure at the top level.
The talented 28-year-old extended his grand slam duck to 11 matches with a first-round loss at the US Open, admitting he was being plagued by doubts.
"He's so impressive in training, he works harder than anyone," Rafter said of Matosevic.
"He prepares himself well. He's just got his own mental demons he has to overcome."
Hewitt, coming off his run to the last 16 at the US Open, will face world No.70 Lukasz Kubot in the opening singles match on Friday (starting 2400 AEST).
Tomic will then take on 113th-ranked Michal Przysiezny, who replaces world No.14 Janowicz.
Wimbledon semi-finalist Janowicz on Thursday succumbed to an ongoing back problem that hampered him during a short first-round exit at the US Open.
Hewitt will team up with Chris Guccione in the doubles on Saturday.