Barcelona edged back to the top of LaLiga on Saturday night but Iago Aspas' 88th-minute equaliser for Celta Vigo cost them two crucial points as they were held to a 2-2 draw.
Barca were looking to capitalise on playing first, with rivals Real Madrid not in action until Sunday's trip to Espanyol.
A Luis Suarez brace, either side of Fedor Smolov's 50th-minute equaliser, had them on course to do so but Aspas struck late in what could be a crucial moment in this tight title race.
Goals from Raul Garcia, Oihan Sancet and Asier Villalibre helped Athletic Bilbao to a 3-1 win over Mallorca in the afternoon match.
Bayern Munich lifted the Bundesliga trophy in an empty stadium as they ended the campaign with a 4-0 win over Wolfsburg.
Kingsley Coman, Mickael Cuisance, Robert Lewandowski and Thomas Muller were all on the scoresheet for the newly-crowned champions.
Chelsea-bound Timo Werner struck twice as RB Leipzig won 2-1 at Augsburg, moving them within three points of second-placed Borussia Dortmund who suffered a shock 4-0 home defeat to Europa League-chasing Hoffenheim.
Andrej Kramaric scored all four goals for the visitors, the last of them a 50th-minute penalty.
Borussia Monchengladbach made certain of the final Champions League spot with a 2-1 win over Hertha Berlin as Jonas Hofmann and Breel Embolo got on the scoresheet.
Werder Bremen thrashed Cologne 6-1 to avoid automatic relegation, a fate suffered by Fortuna Dusseldorf after they were beaten 3-0 by Union Berlin to join Paderborn in the second tier.
Paderborn signed off with a 3-2 defeat at Eintracht Frankfurt, while Bayer Leverkusen beat Mainz 1-0 and Freiburg were 4-0 winners over Schalke.
