Portugal Colonial - Murray confident as Davis Cup gears up for last 16

The top two from each group round-robin -- they will be hosted in Bologna, Manchester, Valencia and Split -- will move into the knockout phase in Spain in November.

It is still not certain whether the newly-crowned US Open champion Novak Djokovic will play for Serbia this week - although he is slated to appear in Valencia - but there will be some big names on show, notably former world number one Andy Murray who is in the Great Britain team that hosts a group in Manchester.

World number two Carlos Alcaraz, however, was ruled out of the Spanish team after his semi-final exit at Flushing Meadows.

"I talked to him and his team throughout the US Open," said Spain captain David Ferrer.

"I was there and watched most of his games, but it is true that he ended up very tired, with some physical problems."

With no Rafael Nadal either, Spain will instead be lead by Alejandro Davidovich, currently ranked 25th in the world.

It is Canada, however, drawing on the experience of Denis Shapovalov and Vasek Pospisil, who are ranked at number one in Davis Cup, having won their first-ever title last year.

Canada are one of four teams to qualify automatically, along with last year's runners-up Australia and wildcards Spain and Italy, who will meet the Canadians in a crunch match on Wednesday.

They have been joined by 12 qualifiers -- Chile, Croatia, Czech Republic, Finland, France, Great Britain, Netherlands, Serbia, South Korea, Sweden, Switzerland and United States.

- 'Huge motivation' -

Eleven of the 16 contenders have already won the Davis Cup including Britain who claimed their tenth title with a Murray-inspired victory over Belgium in the 2015 final.

Now ranked 41 in singles after some serious career-threatening injuries and struggling to make an impact in Grand Slam tournaments, 36-year-old Murray is craving one last tilt at a major title.

"I do genuinely believe the team can win the event," he said at the team press conference on Monday.

"That's huge motivation to be a part of it. I want to help the team in any way I can, whether that's on the court or off. We'll see what happens."

He has good support from world number 17 Cameron Norrie, Dan Evans (27th), doubles specialist Neal Skupski and 21-year-old Jack Draper, who was called up after reaching the fourth round of a Grand Slam for the first time in New York.

There are two singles matches in each tie and a doubles, all played on the same day, reducing the likelihood of doubling up.

Another old favourite Stan Wawrinka, 38, who delivered the Davis Cup for Switzerland alongside Roger Federer in 2014, is back in the Swiss line-up alongside 21-year-old Dominick Stricker who made the last 16 at Flushing Meadows.

The US, who won the last of their 32 Davis Cups in 2007, will be led by Francis Tiafoe and Tommy Paul while South Korea will be aiming to reach the quarter-finals for the first time.

Davis Cup groups:

Group A, Bologna: Italy, Canada, Sweden, Chile

Group B, Manchester - Great Britain, Australia, France, Switzerland

Group C, Valencia: Spain, Serbia, South Korea, Czech Republic

Group D, Split - Croatia, United States, Netherlands, Finland

J.V.Jacinto--PC