The teams exchanged buckets during the first four minutes of the second quarter. Harrison Barnes, who shot 9-of-25 from the field and 2-of-9 from three, made a foul shot to bring the Mavericks within two with 7:57 left in the quarter.
That's the closest they would get.
The Sixers embarked on a 14-0 run shortly after to push the lead to 50-34. Philadelphia led 61-48 at the half behind Robert Covington's eight points in the quarter. The team shot 58% in the first half and had 20 assists, eight of those by Simmons.
Sharpshooters Redick (seven points) and Marco Bellinelli (four points) paced the Sixers in the beginning of the third before Ersan Ilyasova closed it out with seven straight points. The Mavericks once again cut the lead on a 13-2 run after a layup by Maximilian Kleber. Ilyasova drilled a three and then grabbed a loose ball and dropped it in the basket to end the quarter and push the lead to 85-76.
Markelle Fultz hit a 15-foot jumper to begin the fourth and the Sixers led by double-digits the rest of the way. Furkan Korkmaz, TJ McConnell and Justin Anderson entered the game for the first time with two minutes left as the game was out of reach. Philadelphia outscored Dallas 24-21 in the quarter to preserve a 109-97 victory.
Philadelphia shot 46-91 (50.5%) from the field while Dallas shot 40-94 (42.6%). Both teams struggled from three as the Sixers shot 8-27 (29.6%) and the Mavericks shot 11-40 (27.5%). Both teams also struggled from the free throw line as the Sixers shot 9-14 (64.3%) and the Mavericks 6-13 (46.2%). The Sixers outrebounded the Mavericks 52-43 and had eight more assists at 32-24.
The Mavericks looked like a team with only 24 wins in this one. There were many airballs, a corner three off the side of the backboard and all-around hapless play from Rick Carlisle's club. The lone bright spot was rookie guard Dennis Smith Jr. who finished with 20 points, 11 assists, three steals and two blocks.
For the Sixers, Simmons finished with 16 points, seven rebounds, nine assists and four steals. JJ Redick added 18 points and Robert Covington had 15 points, 10 rebounds and two steals.
The win guarantees the Sixers won't finish lower than the fourth seed in the Eastern Conference Playoffs, solidifying home-court advantage. They are currently the third seed and a full game ahead of the idle Cleveland Cavaliers.
The Sixers will travel to Atlanta to face the Hawks on Tuesday at 7:30 p.m. ET.