NICK Kyrgios tested the recovery of a body stressed by a four-pack of tournaments and a long-haul flight in the countdown to Friday's Davis Cup start.
Kyrgios had his first practice at the Queensland Tennis Centre in a closed session on Monday afternoon after earlier receiving massage to his right forearm and right knee as he sat courtside and watched his teammates practise.
Kyrgios and American Jack Sock, the top-ranked players in the quarter-final teams, arrived in Brisbane after playing last week's Miami tournament.
The Australian No.1 undertook four tournaments in the past six weeks, netting him three semi-finals and a quarter-final in a run that underlined a consistency born, he admits, of better application to his training.
Kyrgios said last week he had trouble with the patella tendon in his other knee, his left, "pretty much my whole career''.
Australian team physio Ivan Guttierez treated Kyrgios for a few minutes as he watched likely doubles pair John Peers and Sam Groth practise.
While none of his four players are known for snaring opponents into long rallies, American captain Jim Courier will be aware that Kyrgios has been found wanting when tested by the best-of-five set format which can frustrate him and deplete his energy.
Courier said the Americans would not be playing to get under Kyrgios's skin.
"That's for Lleyton (Hewitt) and Nick to worry about. Our job is to do what's on our side of the net,'' Courier said.
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