"That was ugly early," Nowitzki said. "We didn't really get any stops.
"I thought our bench really saved us," Nowitzki added. "Some nights your starting five just don't have it for whatever reason, fatigue, rhythm or whatever. Our bench was phenomenal."
Nowitzki was the only Dallas starter to score in double figures, with Tyson Chandler, Jason Kidd and Peja Stojakovic all showing the effects of playing more than 30 minutes in Saturday's victory at Washington.
Jason Terry scored 19 points as the Mavericks got 64 points from their reserves to win for the 16th time in 17 games, including nine of 10 on the road.
"This might be the deepest team I've ever played on," Kidd said. "You've got 12 or 13 guys that can start."
Dallas came in having lost two straight against the Raptors, but won for the 12th in 15 meetings.
Ian Mahinmi scored 13 points, and Jose Barea had 12 points and nine assists for Dallas.
Amir Johnson scored 21 points and DeMar DeRozan had 19 for Toronto, which has lost seven of 10 and 20 of 23. Jose Calderon added 15 points, eight rebounds and eight assists.
"They were just picking us apart," Calderon said. "They were just finding the open guy and that's what the good teams do. We stopped them in the first half but in the second we couldn't stop it."
Toronto was without leading scorer Andrea Bargnani (flulike symptoms), while Joey Dorsey (back spasms) missed his third straight game. Ed Davis started in Bargnani's place. The Raptors are 1-5 when Bargnani does not play.
Toronto led by as many as 19 in the first quarter but was unable to maintain that early edge, getting outscored 64-39 in the second half.
"If you come out and aren't ready to play at a high level you're going to get your face smashed in, and that's what happened to us early," Dallas coach Rick Carlisle said. "We took the hit and fought back. Some nights, that's how you've got to win."
Dallas led 75-72 to begin the fourth before blowing the game open with a 12-2 run, including five points each from Nowitzki and Terry.
Toronto made 10 of its first 11 shots and opened a 22-3 lead midway through the opening quarter, while Dallas missed 11 of its first 13 attempts.
"We didn't play any defense for the first five minutes," Kidd said.
Carlisle went to the bench early, bringing in Marion and Terry, and the Mavericks soon closed the gap. A buzzer-beating 3-pointer by Terry trimmed the deficit to 30-24 after one.
Nowitzki scored 16 points in the second but the Mavericks couldn't get any closer, and Toronto took a 57-50 lead into the half.
Dallas opened the third with a 15-4 run, and a slam dunk by Marion with 6:42 left in the quarter put them ahead 62-61, their first lead since scoring the game's opening basket. Marion scored 10 points in the third and the Mavericks never trailed again.
"(Marion) had a tremendous all-around third quarter for us," Carlisle said. "I thought that energized our team and it got us the lead."
NOTES: The 18-point margin of victory was the second biggest of the season for Dallas, second only to a 19-point win over Utah on Feb 23. ... Nowitzki's double-double was his 10th of the season, and he topped 30 points for the ninth time. ... Raptors forward Reggie Evans, out since Nov. 26 with a broken bone in his right foot, took part in his first full practice Saturday but is not yet ready to return. ... Dallas starters scored just five points in the first quarter. ... Toronto's James Johnson had seven assists, a career high