AC Milan hold a commanding 2-0 lead after the first leg of their last-16 tie but Saturday's match at the Nou Camp saw normal service resumed as a strong second-half display ended with Barcelona 15 points ahead of Atletico Madrid who play Sunday.
However, it was Sevilla who took the lead through Alberto Botia in the 42nd minute before two goals in eight minutes turned the game on its head.
David Villa equalised when he nodded home in the 52nd minute on his return from a kidney stone operation before Messi scored his 38th league goal of the season eight minutes later.
Gonzalo Higuain scored an 88th-minute winner as Real Madrid came from a goal down to sneak past a gutsy Deportivo La Coruna side with a 2-1 victory.
The hosts, bottom of the league, took the attack to a slightly weakened Madrid side, with Luis Pizzi and Riki causing no amount of problems and it was the latter who broke the deadlock 10 minutes before the interval.
Depor had several chances to extend their lead but were made to rue some poor finishing when Kaka equalised in the 73rd minute, while Higuain sealed victory for the visitors two minutes from time.
Angel Di Maria was then given his marching orders in the 90th minute after picking up two bookings, but it mattered little to the result.
Real Zaragoza missed a great chance to increase the gap between them and the sides in the relegation zone by throwing away a two-goal lead to draw 2-2 with Valencia.
A penalty by Apono and a headed goal by Helder Postiga gave the Aragon side a two-goal cushion that was cancelled out by a double from Jonas.
However, things could have been even worse for Manolo Jimenez's side, who played the final 11 minutes of the game with 10 men after goalkeeper Leo Franco was sent off for handling the ball outside his area.
Elsewhere, Getafe came from a goal behind to claim a 3-1 win over Real Mallorca at the Iberostar stadium thanks to scoring three times towards the end of the second half.
Giovani Dos Santos gave the hosts the lead midway through the first half but everything changed when Getafe were awarded a controversial penalty with 20 minutes remaining.
Diego Castro scored from the spot to equalise and then Adrian Colunga netted twice inside five minutes to condemn Gregorio Manzano's side to back-to-back defeats.
On Friday, Real Sociedad recovered from a goal down to beat Athletic Bilbao 3-1 and claim a first away victory over their arch rivals in over a decade.
Friday's La Liga Result
Saturday's La Liga Results
Sunday's La Liga Fixtures
Monday's La Liga Fixture
Levante vs Osasuna