The Tigers will receive right-hander Grayson Long and a low-level player to be named later in the deal, per Morosi. The Angels also will reportedly receive cash to cover part of Upton's 2017 salary.
Upton, 30, is a four-time All-Star in his 11th major league season. He is batting .279 with 28 home runs and 94 RBIs through 125 games this year.
The former first-round pick in the 2005 amateur draft had reportedly informed the Tigers he would likely opt out of the final year of his contract next season as the team rebuilds.
Upton has not informed the Angels whether or not he will opt out next season, per Morosi.
Maybin, 30, has hit .235 with six homers and 22 RBIs in 93 games this season. His 29 stolen bases are tied for the American League lead with Houston's Jose Altuve.
Long, 23, is 8-8 with a 2.69 ERA in 26 minor league starts in 2017. MLB Pipeline ranked Long as the sixth-best prospect in the Angels organization and the team's third-best pitching prospect.