Returning to the court for the first time since the Australian Open and a hip injury, world number one Nadal leveled the tie for the host Spaniards and setting the record for the longest career Davis Cup win streak along the way.
Spain ended the first day of their quarter-final tie against Germany 1-1 in Valencia.
Rafael Nadal achieved a historical winning streak in the Davis Cup history.
Nadal is on a record run of 23 successive wins in the Davis Cup, having not lost since 2005.
Nadal was swiftly back in the swing of things in Valencia, dismantling Kohlschreiber after Alexander Zverev blew away David Ferrer 6-4 6-2 6-2 to put Germany in front.
The 31-year-old Nadal scarcely put a foot wrong in his return, with created 14 of the thirty winners in the opening set of a lop sided contest.
Rafael Nadal described his return to action as "a day to remember" after the 16-time Grand Slam victor pulled Spain level in their Davis Cup quarterfinals against Germany.
Lucas Pouille fired the French ahead with a laboured 6-3 6-2 4-6 3-6 6-1 win over Andreas Seppi before home favourite Fabio Fognini redressed the balance with a 6-7 (6) 6-2 6-2 6-3 defeat of Jeremy Chardy.
Croatia took the lead against Kazakhstan when world number three Marin Cilic beat Dmitry Popko 6-2, 6-1, 6-2, before Mikhail Kukushkin levelled the tie after a 3-6, 7-6, 6-4, 6-2 victory over Borna Coric.
"I played more aggressively as the match went on".
"It's a great feeling to be back".
In Nashville, Ryan Harrison and Jack Sock can take an unassailable 3-0 lead for the United States and become the first team to seal their place in the semi-finals later on when they face Belgium's Sander Gille and Joran Vliegen in their doubles rubber.
"It's a memorable day, in front of my own crowd". "I am just happy to get the result", said Zverev.
It seemed simple sailing for Pouille in Genoa later he drifted a side Seppi at the opening two collections however, the slugfest went the distance after the German battled back facing of a passionate home audience.