Australia have received a huge boost in their quest to return to the Davis Cup World Group with Polish star Jerzy Janowicz ruled out of this week’s crunch playoff in Warsaw.

Pat Rafter’s side has also made a significant late change for the tie, starting on Friday, with rising teenager Nick Kyrgios named in the squad to replace Marinko Matosevic.

Lleyton Hewitt and Bernard Tomic will lead Australia into battle on day one of the indoor claycourt tie and 18-year-old Kyrgios could make his debut in a reverse singles match on Sunday.

Hewitt, coming off his run to the last 16 at the US Open, was on Thursday drawn to face world No.70 Lukasz Kubot in the opening singles match on Friday.

Tomic will then take on 113th-ranked Michal Przysiezny, who comes in to replace 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.

His withdrawal comes as a welcome development for Pat Rafter’s squad, which is chasing a return to the competition’s top tier for the first time since 2007.

Poland, chasing a place in the top 16 for the first time, gave Janowicz until match eve to prove his fitness but the 22-year-old ultimately made the call himself.

“My participation in matches would pose a threat not only to my health but also to the interest of the team,” Janowicz said in a statement.

“I believe that Michal will successfully substitute for me.”