But the visitors equalized just after halftime through Pereira, who headed in his first goal of the season after a Diego Ribas set-piece.
O'Sullivan, 44, played his match in Milton Keynes, England on Monday with pink nails in an effort to raise awareness for breast cancer research.
The 35-year-old small forward posted a game-high 43 points in a rare 45 minutes of play.
"We were not able to keep up with the aggressive approach of our opponents. We produced no final passes. I tried to switch things up in the roster but nothing helped," said Slovakia's coach Hapal after the game.
Cao Junwei's 10 points in the first quarter provided Shandong with a 21-19 advantage, but Beijing rode on a 13-0 spurt through Tang and Dong Jingxian's combined efforts to go up 51-36 at half-time.
"All I can do is thank them for the confidence they showed in me," said the forward, who came out from the Barcelona youth system, but plays in the Premier League with Wolverhampton Wanderers.
The two-time World Cup winners looked comfortable thereafter - despite managing only two shots on target -- to ensure their campaign started without a hitch.
After the restart, Turkey caught a bright start and restored parity only five minutes into the second half when Ozan Tufan drilled the ball from 18 meters into the top right corner.
The Lakers beat the Miami Heat in Game 6 of the NBA Finals on Sunday night, winning its first championship in a decade.
Oyarzabal had a chance to double Spain's lead early in the second half, but volleyed wide when maybe he should have hit the target and shortly afterwards Luis Enrique made a double chance with Adama Traore and Sergio Canales replaced Dani Olmo and Ansu Fati.
Spain took the lead thanks to its efforts to pin the Swiss back when Granit Xhaka slipped as Yann Sommer tried a short pass out from goal. Mikel Merino collected the ball and fed his Real Sociedad teammate Oyarzabal to beat Sommer on the turn in the 13th minute.