After thumping Paris Saint-Germain 6-1 earlier in the week, FC Barcelona had their title hopes dented, after they suffered a 2-1 defeat to Deportivo La Coruna on Sunday evening.
Barca nearly found an instant response but Luis Suarez's first-time hit from a cut-back was well saved by Lux, before Denis Suarez fizzed a shot wide from a tight angle.
Sergio Ramos' late goal rescued Real Madrid a 2-1 victory over Real Betis to put the Bernabeu club back atop the La Liga table.
The win gives Zinedine Zidane's men 62 points from 26 matches, two points more than second-placed Barcelona who have played an extra game.
Depor went close when a superb half-volley from Joselu was impressively kept out by Ter Stegen at full stretch, Fernando Navarro creating the chance.
Barca got off to a flyer in the second-half as Suarez lashed home a loose ball inside the area to equalise just a minute after the restart.
Faycal Fajr then shifted past Denis at the far post from a whipped cross, but his shot was deflected just over by the Barca midfielder.
Barca reverted to a 4-3-3 formation, with Denis Suarez and Arda Turan replacing Rafinha and Neymar.
In the 74th minute Alejandro Arribas saw his header saved by Ter Stegen and Barcelona were forced to concede a corner.
But the warning wasn't heeded as centre-back Alex Bergantinos headed into the bottom corner from the resulting set piece.
Both Lionel Messi and Luis Suarez wasted opportunities for the visitors and they were punished five minutes before half-time.
- Luis Suarez has been involved in 10 LaLiga goals in his last three clashes against Deportivo (six goals, four assists).
Among other stats, it's the first time Barcelona have lost a match in which Luis Suarez scored.
- Six of Deportivo's last nine goals in LaLiga have been headers, which equates to a league-high 32 per cent of their total haul this season.