A focused Lleyton Hewitt has warned his players they face a stiff challenge to progress to the knock-out stages of the Davis Cup in Madrid.

Hewitt’s Australia side open their campaign against Colombia, who at 18 are the lowest-ranked side in the tournament and fell 2-1 to Canada on the opening day.

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Such is the focus demanded by Hewitt from his players, the captain put them on a media ban on Monday after the team practised for the last time at the Caja Magica venue.

Nick Kyrgios looks set to open the tie, which starts at 0400 (AEDT) on Wednesday against Colombia’s No.2 player Santiago Giraldo, who is ranked 278 in the world – 248 places below the Canberran.

World No.18 Alex de Minaur will then meet Daniel Galan in the second match before top-ranked doubles pairing Robert Farah and Juan Sebastian Cabal take on John Peers who will be partnered by John Millman or Jordan Thompson.

Australia is looking to get off to a good start at the 2019 Davis Cup.

“I don’t think there are any easy teams in the whole competition,” Hewitt said. “It’s such a fine line between three matches instead of five pertie so every match is critical.

“In the group stages there is a chance for the runner-up to come through. It puts even more importance on the singles matches and even a dead rubber in the doubles.

“In terms of that it’s very exciting for the crowd and we are learning on the spot.

“The Davis Cup requires a different nerve and rankings get thrown out of the door.

“You need guys that are going to handle the pressure and expectation of playing for their country.”

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