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MELBOURNE, July 18 (Reuters) - Retiring former grand slam champion Lleyton Hewitt and Sam Groth combined to defeat Kazakhstan in their Davis Cup doubles tie on Saturday and keep Australia's semi-final hopes alive after their young guns flopped in the opening singles.
Australia were 2-0 down after hot-headed tyro Nick Kyrgios and 19-year-old Thanasi Kokkinakis wilted on the grass-courts in tropical Darwin on Friday.
But 34-year-old Hewitt and 68th-ranked Groth ensured the quarter-final would head into a third day by grinding out a tense 6-4 7-6(4) 6-2 win over Andrey Golubev and Aleksandr Nedovyesov.
For Hewitt, who has announced he will quit tennis after the next Australian Open in January, it was especially pleasing.
"It's up there," Hewitt said when asked what the win meant.
"I haven't played too many doubles matches at 2-0 down when the pressure's on.
"Sam and I combined really well today. This is Grothy's first win in a live rubber, so it's fantastic to be out here to enjoy it with him."
The gutsy win from Davis Cup stalwart Hewitt and the much-improved Groth cheered local fans after a tumultuous week dominated by the controversial Bernard Tomic.
Tomic, who was kicked out of the team for an extraordinary outburst against Australian tennis officials in Wimbledon, was charged with trespassing and resisting arrest on Thursday following complaints over a noisy penthouse party at his Miami Beach hotel.
Australia's Davis Cup captain Wally Masur said he might shake up his selections for the reverse singles after Kyrgios and Kokkinakis's struggles on Friday.
"Obviously form and confidence are important," Masur told local media.
"I was really impressed with these two guys (Hewitt and Groth) today.
"They had great clarity; they knew exactly what they had to do with our backs against the wall.
"It was a really good team effort, so I do have decisions to make based on the results over the weekend, and hopefully we get it right."
Masur added that he felt Kyrgios might be feeling the strain after weeks of controversy following his performance at Wimbledon, where he was accused of poor sportsmanship during matches and "tanking", or giving up, during his fourth round exit.
"It takes its toll. I kind of feel sorry for Nick in a way because it was almost a little bit of hysteria about some of the stuff that went on at Wimbledon," Masur said.
"The press cycle just kind of went into overdrive."
The winning team takes a spot in a semi-final against either Britain or France.