A debut win for Billy Harris sealed victory for Great Britain in their Davis Cup opener against Finland in Manchester.

Harris held his nerve in a tight second set against Otto Virtanen to secure a 6-4 7-6 (4) victory and give the hosts an unassailable 2-0 lead in the tie at the AO Arena.

The win coupled with Dan Evans' 7-6 (3) 6-2 success against lowly-ranked Eero Vasa earlier ensured Britain avoided any missteps as they try to book their spot at the last eight event in Malaga in November.

Harris' performance more than justified captain Leon Smith's decision to give US Open semi-finalist Jack Draper extra rest ahead of much tougher-looking ties against Argentina and Canada later this week, with a top-two finish needed in the group.

At 29, Manxman Harris is the ultimate late developer having finally made his way to the upper echelons of the sport over the last 12 months after years spent touring round Europe in a converted transit van.

This was a tricky first match against 23-year-old Virtanen, ranked only nine places lower than Harris at 110 and who played a key role in Finland's surprise run to the semi-finals last year.

Here they were without number one Emil Ruusuvuori through injury, though, and Virtanen's attempts to force a deciding set fell just short.

Harris was in complete control against an erratic opponent until 4-2 in the second set, when he missed multiple chances to secure a double break and was immediately pegged back.

But he withstood pressure to force a tie-break and showed the composure of a seasoned campaigner to clinch the victory.

"I think debut for Great Britain, this probably tops it all so far," said Harris. "It was always going to be tough coming in playing number one with Jack and Cam (Norrie) and people not around. But I thought I went out and played a good match.

"Definitely a few nerves in there, you're not just playing for yourself, you're playing for team and country. But as soon as it got going I felt good out there. A very proud moment and I'm happy I put in a good performance."

Evans' clash with Vasa was a landmark occasion for the British veteran, who by playing in his 26th tie in the competition surpassed Andy Murray to claim joint second place in the British standings alongside Mike Sangster and behind only Bobby Wilson.

He would not have been a bigger favourite in any of his previous 37 rubbers, but Vasa played well above his standing of world number 703 during a tight first set.

"I knew his ranking, which probably made it a bit more difficult, there's a lot more pressure for me to win the match," said Evans, who has slipped to 178 in the world after a difficult 12 months.

"As well as Billy being a debutant, I really wanted to be 1-0 up, just would help him out a bit more. I did well to weather the storm, and it was pretty comfortable in the end."

The 34-year-old made his Davis Cup debut way back in 2009, and he picked out victories over Slovakia and Russia a decade ago when Britain were stuck in the lower reaches of the competition as highlights.

"It's a pretty good thing to have," he said of moving past Murray. "I've enjoyed every tie. One which really was amazing was when we beat Slovakia, and obviously the Coventry one (against Russia).

"The early days were pretty good when we weren't very good. We got some big wins, and then there's so many more after that, obviously last year was really good.

"Every week is great, it's amazing to be part of the team. I don't know how many more times I'll get a chance so I'll carry on enjoying it."