Barcelona's run of poor form continued following a surprise 1-1 draw at home to Athletic Bilbao on Saturday.
Lionel Messi and Sergio Busquets started on the bench as Barcelona stretched their winless run to three La Liga matches.
Messi's arrival changed the game in Barcelona's favour but Ernesto Valverde will rue more points dropped in La Liga as he switches attention to the midweek clash with Tottenham in the Champions League.
"I have to judge the games we have coming up and we have four games in the space of 10 days, I have to think about what might happen and I thought Leo and Busquets had to rest, knowing that we have a very tough game on Wednesday and we have a large squad," Valverde told a news conference.
"I know it was a risky decision but if it had gone well no-one would have even asked me about it. When I take a decision like this, I think in the best interests of the team and the club. Sergi Roberto got injured today, imagine if Messi had."
Oscar De Marcos' goal just before the break looked to have made it back-to-back defeats for Barcelona following their midweek loss to Leganes but Munir El Haddadi equalised seven minutes from time.
Luis Suarez squandered a good opportunity for the hosts in the first half and Barcelona found visiting goalkeeper Unai Simon in inspired form throughout.
De Marcos stunned the Camp Nou following a set piece just before half time to give Bilbao the lead and Valverde didn't waste too long in trying to rectify the situation after the break.
Just 10 minutes after the restart, Messi was sent on for Arturo Vidal as Barcelona looked to find a way back into the match. And after Philippe Coutinho hit the bar on 60 minutes, Messi's free kick was headed off the line as Bilbao battled bravely to keep their lead in tact.
They could have doubled their lead shortly after Messi went close, but Nelson Semedo's last ditch tackle stopped Inaki Williams when he was through on goal.
Messi's arrival brought added impetus from the home side and once again he went close, hitting the post 13 minutes from time. But just as it appeared Valverde's men were set for a second successive defeat, Messi's cross found substitute Munir and he converted from close range to make it 1-1.
It rescued a point for Valverde but the 1-1 draw meant it was the first time Barcelona had not won in three matches since his appointment. Messi was also booked after the final whistle for dissent as the home side's frustration spilled over.
Barca striker Suarez was critical of his side's performance and their continued dependence on Messi.
"He is the best in the world but we can't rely on Leo to always sort everything out for us," the Uruguayan said.
"The other players here are here on our own merits and we can't depend on him or Busquets, we should have been winning when they came on to the pitch."