Great Britain clinched a return to the elite Davis Cup World Group as Andy Murray steered the team to an unassailable 3-1 lead over Croatia.

Murray made a mockery of any injury concerns on the clay of the Stadion Stella Maris in Umag against his overmatched opponent, coming through 6-4 6-2 6-4 against Ivan Dodig to complete a memorable week for Britain.

The world number three's victory ensured the team, captained by Leon Smith, are back in the elite World Group for the first time since 2008.

Murray said on Eurosport afterwards: "I was nervous. I wanted to try and finish the tie, it was a big match for us, we wanted to try and get back into the World Group, the guys have had some big wins this year and I didn't want to let the team down.

"I've dealt with enough pressure around Wimbledon time and those sorts of matches to know how to get through it and how to conquer the nerves and fears that you have before you go out on the court.

"I'm glad I managed to finish it off because he fought extremely hard and nearly got back into it at the end."

The prospect of facing the world's best tennis nations appeals to Murray, who added: "I'm looking forward to it, it'll be interesting. We get to play against some of the biggest countries in the world against top teams and top players.

"It's exciting for all of the guys and hopefully I'll be a part of it next year."

Britain held the advantage coming into Sunday's reverse singles after Murray and Colin Fleming won in the doubles 24 hours earlier against Dodig and Mate Pavic.

There were worries over Murray's back injury, which had left him a doubt for Saturday's doubles match.

The Scot, however, was largely in imperious form throughout, starting when he broke Dodig in the very first game after the Croatian limply dumped a backhand into the net.

The world number 35 got into the groove to level the scores at 2-2, but Murray immediately broke again, thanks in part to two Dodig double faults and duly closed out the opening set in 47 minutes.

A fantastic backhand volley saw Murray break in the third game of the second set and the 26-year-old saved two break points to establish a 4-2 lead.

Errors were creeping into Dodig's game and Murray secured a double break before opening up three set points, taking the second after his opponent hit a looping return out.

Dodig was immediately broken at the start of the third set after netting a backhand to put Murray firmly in the ascendancy and the Wimbledon champion clinically sealed victory, despite a minor controversy while serving for the match.

At 30-all, a crosscourt forehand from Dodig looked to have caught the line but Murray called for an over-rule after pointing to the mark in the clay and the verdict was given in his favour, to the chagrin of the Croatian and the partisan crowd.

Murray took his first match point to cat calls in Umag and admitted afterwards that it was character-building.

He added: "It's different. The atmosphere was pretty hostile at the end. You don't get that in grand slam matches, the crowd are fairly fair but that's something special about Davis Cup.

"It's a character builder, you don't have to deal with that for the rest of the year and also you're playing for the team and your country so it's tough."

Team captain Smith was ecstatic about the performance of Murray.

"It's amazing, I think Andy put in an incredible performance, my voice is gone from shouting. The crowd were absolutely brilliant," Smith said.

"Actually I quite liked the way it ended with that point. I think that'll set us up as a good experience for next year which might bring us some of those atmosphere in crowds.

"I think from start to finish, Andy was exceptional."

Murray's win ensured Dan Evans' match against 16-year-old Borna Coric became a dead rubber.