Lleyton Hewitt cast doubt on Bernard Tomic's Davis Cup future after he withdrew from the Australian team to play Czech Republic, while Canada will be without Milos Raonic when they face Great Britain.
Tomic opted against playing for his country in Melbourne next week, citing scheduling reasons, although reports have claimed the world number 27's camp are not happy with Tennis Australia due a funding dispute with his sister, Sara.
Australia's Davis Cup captain does not agree with Tomic's decision to miss the tie and said it is down to 24-year-old to decide if he wants play any further part in the team event.
Hewitt said: "It's obviously disappointing not to have him available because he has played so well for Australia in the past and been a regular in the team.
"He needs to make decisions for his reasons, but I'm not going to go out and beg guys to play for their country. In saying that, I think we've got a team that want to go out there and lay it on the line for their country.
"It's his decision ... certainly I don't agree with it, but we've got to move on."
Asked if Tomic still has a Davis Cup future, a frank Hewitt added: "I'm not sure ... I really don't know.
"This is his decision - not mine - I don't know the full extent of how serious he is to play Davis Cup for Australia. You'd have to ask him."
Meanwhile, Canada will be without Raonic against 2015 champions Great Britain after the world number three sustained an adductor injury at the Australian Open, with Peter Polansky called up as his replacement.