The Spanish champions have taken a single point from their three away games this season, failing to win any of their past seven matches on the road in all competitions.
Ramon Azeez and Alvaro Vadillo struck to condemn Barca to defeat at Nuevo Los Carmenes on Saturday, a stunning result that moved newcomers Granada top of the table on goal difference.
Barca, meanwhile, are lagging behind in seventh spot with seven points from as many games.
However, similar troubles for Real Madrid and other elite LaLiga clubs mean they are only three points behind the leaders.
7 - With seven points from five games, Barcelona have made their worst start to a LaLiga season since 1994/95 (also seven – three points per win). Worry. pic.twitter.com/6VligaBXmq— OptaJose (@OptaJose) September 21, 2019
The last time they made such a poor start to a league campaign was in 1994-95, towards the end of the Dream Team era under legendary coach Johan Cruyff.
With nine goals conceded, moreover, Valverde's men have equalled their worst defensive start to La Liga since 1996-7.
The Catalans' woes are in direct contrast to the dream start to the season newly promoted Granada are enjoying.
With 10 points from their first five games, the Andalucians have made their best start ever in a Liga campaign, and are halfway to the tally they managed in their last stint in the top flight in 2016-17, when they managed a paltry 20.
Granada took the lead after just 64 seconds through Ramon Azeez, the fastest scorer against Barca since Karim Benzema, who broke the deadlock for Real Madrid in December 2011 21 seconds in.
They then doubled the advantage when Alvaro Vadillo converted from the penalty spot, the Blaugrana's third conceded in their last four outings - as many as in the previous 61 matches.
La Liga's surprise package will hope to continue their fine form on Tuesday away to Valladolid, hours before Barca look to get back on track at home to Villarreal.