Although Belgian striker Robert Lewandowski scored the decisive goal in the 61st minute, it was Yamal who stole the spotlight at the Lluis Companys Olympic Stadium.
Barcelona president Joan Laporta defended his handling of the Dani Olmo registration issue and lashed out at enemies attacking the club in a fiery speech on Tuesday.
Record 31-time Copa del Rey winners Barcelona were drawn at home against Real Betis in the last 16 on Wednesday.
Barca remain on 34 points and lead second-placed Real Madrid by four but their rivals now have two games in hand, while the victory moved Las Palmas up to 14th place on 15 points.
Barcelona cited UEFA rules preventing clubs from changing stadiums during the Champions League's opening phase and "the logistical difficulties and extra costs" if they kept open two grounds at the same time.
A product of Barcelona's youth academy, Bernal has made three league appearances since his debut for the senior team in their LaLiga opener against Valencia.
Barcelona's next away game is at Serbian club Crvena Zvezda in Belgrade on November 6.
Olmo will miss Barcelona's opening Champions League matches against Monaco and Young Boys.
The German coach took charge of his first home match since he was appointed in May.
Although Belgian striker Robert Lewandowski scored the decisive goal in the 61st minute, it was Yamal who stole the spotlight at the Lluis Companys Olympic Stadium.
Barcelona president Joan Laporta defended his handling of the Dani Olmo registration issue and lashed out at enemies attacking the club in a fiery speech on Tuesday.
Record 31-time Copa del Rey winners Barcelona were drawn at home against Real Betis in the last 16 on Wednesday.
Barca remain on 34 points and lead second-placed Real Madrid by four but their rivals now have two games in hand, while the victory moved Las Palmas up to 14th place on 15 points.
Barcelona cited UEFA rules preventing clubs from changing stadiums during the Champions League's opening phase and "the logistical difficulties and extra costs" if they kept open two grounds at the same time.
A product of Barcelona's youth academy, Bernal has made three league appearances since his debut for the senior team in their LaLiga opener against Valencia.
Barcelona's next away game is at Serbian club Crvena Zvezda in Belgrade on November 6.
Olmo will miss Barcelona's opening Champions League matches against Monaco and Young Boys.
The German coach took charge of his first home match since he was appointed in May.
Barcelona signed Spain star Dani Olmo from RB Leipzig on Friday for a reported 60 million euros ($65 million).
