Marion, a four-time All-Star, has been scratched from Wednesday's home game against the Toronto Raptors and will not travel with the team to New York and Charlotte later this week.
The 34-year-old, who sprained his left medial collateral ligament in the third quarter of Dallas' 114-91 win over the Portland Trail Blazers on Monday, will be re-evaluated next week.
Marion is averaging 8.0 points, 9.0 rebounds and 3.3 assists after four games.
The 3-1 Mavericks began the season knowing they would be without 11-time All-Star Dirk Nowitzki for at least six weeks after the German forward had knee surgery last month.
Charlotte Bobcats starting guard Gerald Henderson is expected to be sidelined for two to four weeks because of a sprained left foot.
Henderson, who is averaging 12.5 points, 3.0 steals and 2.5 assists after two games this season, suffered the injury during Saturday's 126-99 loss to the Dallas Mavericks.
Either Ramon Sessions or Ben Gordon will replace Henderson in the starting five for Charlotte's home game against the Phoenix Suns on Wednesday.
Los Angeles Lakers point guard Steve Blake was fined $25,000 on Tuesday for "directing inappropriate language" at a courtside fan.
Blake's remarks toward the fan occurred with 29.2 seconds left in the fourth quarter of the Lakers' 105-95 loss to the Los Angeles Clippers last Friday at the Staples Center.
The nine-year NBA veteran hit two of six shots and had eight points and three turnovers before fouling out and arguing with a man in the first row.