Darwin NT, Australia, 19 July 2015 | AAP

Big-serving Victorian Sam Groth has replaced Nick Kyrgios for Sunday’s Davis Cup singles clash against Kazakhstan in Darwin.

And Lleyton Hewitt is also on track to play on Sunday as Australia attempt to keep their title hopes alive.

Australia trail 2-1 in the tie after Kyrgios and Thanasi Kokkinakis lost their singles matches on Friday, before Groth and Hewitt combined to win Saturday’s doubles.

Groth will take on Kazakhstan’s top-ranked male, world No.63 Mikhail Kukushkin.

If he wins that to level the tie, Hewitt is expected to replace Kokkinakis for the deciding singles rubber.

> follow the live scores and find more information on our AUS v KAZ tie page