The Orlando Magic stunned the Detroit Pistons 112-101 on Sunday as the reigning champion Oklahoma City Thunder and Boston Celtics opened the NBA playoffs with big wins.The Thunder, trying to become the first team since the Golden State Warriors in 2017 and 2018 to repeat as champions, came out firing in a 119-84 victory over the Phoenix Suns.The Celtics, seeded second in the Eastern Conference behind Detroit, dominated the Philadelphia 76ers 123-91.