Britain book Davis Cup finals berth with tie-break win over France
The British duo came back from a set down to beat French pair Nicolas Mahut and Edouard Roger-Vasselin 1-6, 7-6 (7-4), 7-6 (8-6) in front of 13,000 fans in Manchester as nerves faltered on both sides of the net.
In a contest of almost three hours, France came close to sealing their passage and will look back at four failed match points and a series of unforced errors.
Skupski, who won the Wimbledon men's doubles with Dutchman Wesley Koolhof this year, said: "I don't know how we've won that fight, (just with) sheer fight. "Incredible effort from Dan to come out and win this match with me.
"First set it wasn't too good. We regrouped, took a toilet (break) and fought as hard as we could. The rest is history and we're off to Malaga."
Britain join Italy, Serbia, Canada, Czech Republic, Netherlands, Finland and Australia in the finals in Malaga in November.
In the opening rubber, Evans fought back from a set down to see off French teenager Arthur Fils 3-6, 6-3, 6-4 and take a 1-0 lead for Britain.
But Cameron Norrie was beaten by Ugo Humbert, leaving the contest level with everything depending on a tense decider in the doubles rubber.
Earlier, Italy became the seventh team to qualify for the final eight with singles wins from Matteo Arnaldi and Lorenzo Sonego giving them an unassailable 2-0 lead against Sweden in Bologna.
Arnaldi, 22, who reached the fourth round at the US Open, saw off Sweden’s Leo Borg 6-4, 6-3 in one hour and 22 minutes.
Sonego then overcame Elias Ymer 6-4, 6-4 to move Italy 2-0 ahead.
Victory means the Italians, who only needed to win one of their ties to advance ahead of Chile, progress alongside group winners and defending champions Canada.
Italy have now advanced to the Davis Cup quarter-finals five times since 2016.
