Lionel Messi was left in Catalonia for the penultimate game of the term, with Barça heading to South Africa for a high-profile friendly in midweek, before returning to see out La Liga campaign next weekend.
And the 54-year-old's decision seemed to backfire as Blaugrana found themselves 5-1 down in Valencia with less than an hour played - the first time they had conceded five since 2003.
But Barcelona battled back through a Philippe Coutinho hat-trick and a Luis Suarez penalty. However, it was not enough to avoid tasting defeat for the first time this season.
And while speaking after the match, Valverde revealed his anger (as quoted by the Daily Express). Although he admitted he is now looking forward to his side's next challenge.
At least Messi will be back for the friendly in South Africa in midweek.— Samuel Marsden (@samuelmarsden) May 13, 2018
“I’m very angry that we didn’t finish the season unbeaten, but I won’t dwell on it. We have to look forward,” Valverde said.
“It was an absorbing game, with great finishing from our opponents. We reacted well, went forward, cut the deficit and even came close to drawing several times.
“The match was decided by counterattacks, especially during a crazy 10-minute spell in the second half, when they scored three goals. Our opponents are currently the best team in the league through their intensity and accuracy in front of goal, not only in this game but also others like against Leganes.
“They also played very freely because they were no longer burdened by tension. You have to acknowledge what they’ve achieved, although it’s strange that we conceded five goals for how the season’s gone.”