Jayson Tatum scored 24 points, Derrick White added 23, including Boston’s first 11 of the third quarter, and the Celtics beat the Dallas Mavericks 122-107 on Saturday night in the first meeting between the teams since the NBA Finals. Jaylen Brown added 22 points as the defending champions bounced back from a 21-point loss to the Los Angeles Lakers on Thursday night, their most lopsided defeat this season. The Celtics shrugged off an early 16-6 deficit and led by as many as 25 points in the third period. White scored 16 in the period. Kyrie Irving scored 22 points, Quentin Grimes added 20 off the bench and Daniel Gafford had 19 points and matched a season high with 15 rebounds for the Mavericks, who are 5-11 since superstar Luka Doncic was sidelined with a calf strain on Christmas Day, The teams will complete their two-game season series Feb. 6 at Boston. Takeaways Celtics: Kristaps Porzingis scored 18 points in his first game back in Dallas following the Feb. 10, 2022, trade that sent him from the Mavericks to Washington. Porzingis sat out his four previous visits, including Games 3 and 4 of last year’s finals, with injuries. Mavericks: Down to two centers, backup Maxi Kleber fractured his right foot and left the game late in the third quarter. Kleber will be re-evaluated next week. Key moment With Dallas trailing by 21 points in the final minute of the third quarter, the home fans had to fend off the first of multiple “Let’s go Celtics! Let’s go Celtics!” chants. Key stat The Celtics, NBA leaders in 3-pointers made (17.8) and attempted (48.9) per game, went 2 of 8 in the first period but finished 20 of 52. Up next Both teams will be home Monday, the Celtics against Houston and the Mavericks vs. Washington.