Ansu Fati became the youngest Barcelona player to score in La Liga but his side were held to a 2-2 draw away at Osasuna on Saturday.
Ansu -- aged 16 years and 298 days -- came on as a substitute and scored his first professional goal after six minutes to equalise for the Spanish champions.
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Another substitute Arthur Melo scored his first goal for Barca in 45 appearances with a curling effort to put the visitors ahead.
The hosts took the lead early as Roberto Torres smashed a volley past Barca goalkeeper Marc-Andre Ter Stegen.
Barca dominated possession throughout and went ahead through strikes from Ansu and Arthur in the second half.
With less than 10 minutes to go, the hosts were awarded a penalty when the ball struck Gerard Pique's arm and Torres grabbed his second from the spot.
Ernesto Valverde's side have started the campaign with one win, one defeat and one draw.
Before the match, there was a minute's silence held in memory of former manager Luis Enrique's daughter who died from bone cancer.