Caught between obscurity and the World Group playoffs (WGPOs), the third highest level on the Davis Cup pyramid produced another year to remember, with some of tennis' biggest names flying their nation's flag. From Sweden and Spain both surviving relegation scares, to Poland's stunning win over Ukraine, 2015 thrilled Europe. In the second of our reviews, we look back at all of the action.
Nadal returns to save Spain
Spain began the Davis Cup year with a bye, due to their high ranking, into the second round of Group I, where the winners progress to the World Group Playoff. Drawn to face Russia, who had demolished Denmark in round one, a depleted Spanish team blew a 2-0 lead as they were dumped into the Group I playoffs.
Bereft of Rafael Nadal, who hadn't played since 2013, and David Ferrer, the Spaniards were led out by Tommy Robredo, in his first match since 2010 and thirteen years since making his Davis Cup debut. Backed by Pablo Andujar, they got off to a perfect start as they stolled to the first two singles matches without losing a set to the inexperienced Karen Khachanov and Andrey Rublev.
Going into the Doubles on day two, the Spanish could have sealed their return to the WGPOs before the final day. But instead, despite leading by a set on two occasions, they were defeated by the Russians who gave themselves a chance of clawing back the tie.
They did so in stunning fashion as Evgeny Donskoy, subbed in for Khachanov, upset Robredo in a tight four setter before teenager Rublev swatted aside Andujar in straight sets to send Russia into the WGPOs and Spain crashing down towards relegation.
So with the daunting prospect of being relegated to Group II for the first time ever in their history, having been mainstays in the World Group or WGPOs since 1996, Spain knew they would have to win against Denmark when the two sides met in Odense in September.
However, Spain had a major card up their sleeve, as Rafael Nadal, fully fit and fresh, returned to the team for the first time that year and he was joined by David Ferrer, Fernando Verdasco and Roberto Bautista Augt, in a team of only top fifty players.
This would prove decisive, as they called upon all of their strength and experience to easily dismantled the Danes. Racing into a 2-0 lead without dropping a set, a doubles team which included Nadal sealed the tie before the final day with a 3-1 win over Thomas Kromann and former Wimbledon Champion Frederik Nielsen.
The huge celebrations from the Spanish demonstarted just how important a victory it was, and one of the proudest nations in the tournament's history will look to reclaim its place within the elite in 2016.
However, the Danish misery was far from over as they faced the daunting the task of having to now overcome fierce rivals Sweden in a relegation playoff or else they would tumble back down to Group II.
Swedes see off rivals in tight decider
At one time, Sweden were the greatest team in the competion, dominating from the late 70s until the early 90s, but now they often find themselves continually clawing to their past glories. As they headed south to face their rivals in a repeat of 2013's relegation playoff, there was the very real chance they could drop to Group II for the first time ever.
Without a single top 100 player in the field, the Swedes got off to the perfect start on day one as Markus Eriksson defeated Andreas Bjerrehus in five thrilling sets, before the talented teenager Mikeal Ymer shocked Nielsen in his first ever Davis Cup match.
However, the Danes refused to go down without a fight as they battled to victory in the doubles, winning in a fourth set tiebreak, before Nielsen made amends for his opening day defeat by beating Eriksson and taking the tie to a decider.
And what a decider it would prove to be, as the teenagers Christian Sigsgaard and Ymer produced a pulsating five set decider, in which the Swede came out on top. Having both been born after Sweden's last triumph, the match perhaps signalled a fresh start in Scandinavian tennis. Rushing into a two-set lead, Ymer looked on course to cruise to the decider, before Sigsgaar bounced back to take it to a fifth and despite the crowd vocally backing him, it wasn't enough as the Danes were relegated to Group II. They will be joined in Group II by Lithuania who were swatted aside 5-0 by Slovenia.
Wow I can't describe my feelings with words right now... So happy for my team and Sweden right now, we did it!!
At the other end of Group I, the Dutch and Slovaks fought through to the WGPOs
Whilst most of the attention may have gone to Spain and Rafael Nadal for their terrifc victory, way back in July of this year four nations escaped Group I to secure their shot at reaching the World Group. As mentioned, Russia were one of the teams to do so in beating Spain, but they were joined by Holland, Slovakia and Poland.
The Poles reached the WGPOs for the first time since 2013 and were looking to finally overcome that hurdle and reach the World Group, but first they would have to win in their second round mathc. They did so by beating Ukraine at home as they overcame their opponent's higher ranked players to upset the odds.
Recovering from a match down, the Poles sealed their victory before the final singles rubber with Jerzy Janowicz's win over Sergiy Starkhovsky in four sets.
Former World Group team Holland joined the Poles as they made their annual yo-yo between the World Group and Group I by defeating Austria 3-2. Having played in the World Group during 2014, the dutch looked eager to make the return to the elite of world tennis, as they proved too good for their opponents.
Relying upon a team of experience, led by the Robin Haase, the dutch won the decisive doubles rubber when the score was tied at 1-1 before Haase defeated the talented Dominic Theim to seal their place in the WGPOs.
The final European WGPOs spot went to former runners up Slovakia, as they recovered from 0-1 down to defeat the Romanians away from home. Runners up in 2005 to Croatia, Slovakia reached the WGPOs for the second year running with a 3-2 win.
In the WGPOs they would face Poland, whilst Russia were drawn against Italy and the Dutch against Switzerland.
But just how did they get on? Tune in to the next of our reviews of the Davis Cup 2015 to find out.