Lionel Messi has scored against 10-man Granada to give Barcelona manager Quique Setien a 1-0 win in his debut for the Spanish league leaders on Sunday.
Granada had kept Barcelona in check and hit the post moments before German Sanchez was sent off with 20 minutes to play after receiving a second yellow card for fouling Messi.
Messi soon exploited Granada's re-organised defence with a sharp pass to Antoine Griezmann inside the area. Griezmann squared the ball for Arturo Vidal, who used his heel to roll it on for Messi to slot into the corner of the net for the 76th-minute winner.
Setien, who last coached at Real Betis, was hired by Barcelona last Monday after the club fired former boss Ernesto Valverde following a loss in the Spanish Super Cup semifinal to Atletico Madrid.
The result means Barcelona stay ahead of Real Madrid on goal difference, eight points clear of third-place Atletico Madrid after 20 of 38 rounds.
Elsewhere, Croatian striker Ante Budimir scored twice as Mallorca moved out of the relegation zone with a 4-1 win against 10-man Valencia.
Antonio Raillo and Dani Rodriguez also found the net as Mallorca recorded their first win in seven rounds and their biggest victory since they were promoted to the top flight this season.
Valencia's Dani Parejo was sent off after a second yellow card in the 51st minute and Ferran Torres scored Valencia's late consolation goal as they fell to their first loss in six rounds.
Espanyol hung on for a 2-1 win at Villarreal to end a run of nine league games without a victory that dated back to October.
David Lopez and new signing Raul de Tomas, making his league debut, scored with headers for Espanyol. Santi Cazorla converted a penalty for Villarreal.
Espanyol remain in last place but climbed to within four points of safety after a second consecutive match taking points under new coach Abelardo Fernandez.
Mid-table Real Betis beat Real Sociedad 3-0 at home thanks to goals by Borja Iglesias, Joaquin Sanchez, and Sergio Canales.
The loss left Sociedad in sixth place, right behind Getafe.
Raul Garcia's 76th-minute penalty rescued a point for eighth-placed Athletic Bilbao at home to third-from-bottom Celta Vigo. Rafinha opened the scoring for the visitors.