Arsenal's exuberant and emotional celebrations at the full-time whistle in Lyon were 18 years in the making.

That is how long it has been since the Gunners last contested a Champions League final and just six months ago doing so again looked like a pipe dream.

But following what has often been a tumultuous campaign, with poor results and a change of manager, all is well again in North London.

Arsenal produced a magnificent comeback to win 4-1 against eight-time champions Lyon in France, overturning a 2-1 first-leg deficit to reach the Champions League final where they will face holders Barcelona.

It was an uncharacteristically poor performance from hosts Lyon, with an own goal in the opening five minutes setting the tone for a tough night.

But Mariona Caldentey's superb strike was followed by goals from Alessia Russo and Caitlin Foord, securing an impressive and deserved victory for the Gunners.

"We were unbelievable in a high-pressure moment against a top opponent," said boss Renee Slegers.

"How calm we were - there's so much work put into this game, I'm so happy.

"Delighted for everyone. Its euphoria, such a special moment. So happy and we need to celebrate these special moments but also stay humble and we get ready for the next one."

It has been a long journey to the final for Arsenal.

From round one of qualifying against Rangers back in September to now, they have played in 14 Champions League matches this season. No team has ever done so in this format.

With Chelsea looking set to lift the Women's Super League title for a sixth consecutive year, Arsenal seemed in danger of fizzling out.

Instead, they have managed to do what Chelsea could not - overturn a first-leg deficit against top European opposition to reach the Champions League final.

Granted, Lyon were not at their best in what boss Joe Montemurro called a "perplexing" and "inexplicable" performance.

But Arsenal capitalised on that and were able to assert some dominance to win a two-legged European semi-final away from home for the first time.

The outpouring of emotion at full-time from Arsenal's veteran player Kim Little, who turns 35 in June, said it all.

Alongside Spaniard Caldentey in midfield, Little dominated - controlling the game in attack and defence with her silky passes and tricky footwork.

"I can't believe she's still playing at this level and getting better and better. It's because of her attitude and application," former Chelsea forward Karen Carney said on TNT Sports.

"Her and Caldentey's relationship - having the licence to go and attack, using her body, her calmness keeping the ball.

"When she got emotional at the end, I've never seen that. She's a classy player and person."

Spurred on by their 500 or so travelling fans, who had been allocated a section on their own high up in the top tier of the 60,000-capacity stadium, Arsenal were clinical, scoring four goals from their six shots on target.

"I think we played really well and created the momentum," said Foord, who scored their fourth goal.

"We finished our chances, which is so important. We won the ball higher up in crucial areas and I think we rattled them a bit. We got them in good areas and finished our chances."

The last time Arsenal reached the Champions League final, Slegers was playing in the Gunners' academy.

Eighteen years later, the former midfielder will become just the second Arsenal women boss to lead out the team in the final of Europe's top competition.

The 36-year-old says she can't remember much about the 2006-07 campaign which saw Arsenal win a historic quadruple, but recalls watching the final on television.

"I remember back then there were very few role models, I couldn't watch much on football on TV in the Netherlands. I came to England and saw them training and seeing them perform in the Champions League was very inspiring," she said.

Just seven months on from replacing Jonas Eidevall, then as interim boss, and four months on from being appointed permanently, Slegers has completely turned Arsenal's fortunes around.

In a season of change and at times turmoil, she has managed to not only steady the ship but also do what Eidevall could not: get the best out of a squad that, on paper, has long looked ready-made for success.

"If you look back at the early parts of the season, Arsenal had some really difficult moments, certainly when Eidevall was in charge," said former England midfielder Fara Williams on TNT Sports.

"Slegers has given them something different. You've seen a real shift in the players.

"They've been the strongest WSL team of late. They were phenomenal today."

Russo had scored just one goal and registered one assist in the first nine games of this season but is now Arsenal's top scorer with 19 goals in all competitions.

Chloe Kelly has also proved a revelation. Struggling for minutes at Manchester City she had looked almost down and out, but a January move to the Gunners has reinvigorated her and she looks back to her best.

"The manager has been a revelation," said Carney. "I'm thrilled for them. Arsenal are back now. I really hope they win it."

Arsenal may have twice come back from first-leg defeats to win ties against Real Madrid and now Lyon, getting their tactics right at the second time of asking, but their toughest task - against Barcelona in the final - awaits. They know they will have to get it right first time.

The holders have contested five of the past six Champions League finals, winning three of them, while their two defeats came against Lyon.

"It's going to be a tough game, a final, anything can happen," said Foord. "We look forward to it. It's an exciting moment for us, so just can't wait to take them on."

A big challenge but one that could be made easier by Arsenal's former Barca player Caldentey, who has lifted the trophy three times with her former club.

The 29-year-old's experience and know-how shone through against Lyon and she could be seen directing her team-mates throughout the match, dictating where the ball should go.

She has popped up with key goals in key moments, scoring the goal that put Arsenal ahead in the tie in France, her eighth goal in her past 11 Champions League appearances for Arsenal.

Carney said Caldentey is currently "the best player in the WSL" but Arsenal know they will need more than just one world-class performance to get past world-beaters Barcelona.