Love agreed to a four-year contract extension earlier in the day and then produced his 16th consecutive double-double.
The Mavericks became the first two-time loser to Minnesota this season. The Timberwolves downed Dallas Jan. 1 and the Mavericks had gone 10-3 since then.
It was a tie game with 3 minutes left in the third period but Minnesota outscored the Mavericks the rest of the way 35-20.
Ricky Rubio added 17 points for Minnesota and Wayne Ellington had 16.
Jason Terry led Dallas with 17 points.
The Mavericks, who lost at home for the first time in eight games, played again without Dirk Nowitzki. He has been out for contests games with a sore knee.
Members of the 2010-11 Dallas team that won the NBA title received their championship rings in a pregame ceremony.