Mattingly has managed the Marlins for two seasons, compiling a 156-167 record during that time. In 2017, Miami finished 20 games behind the National League East champion Washington Nationals, and the Marlins missed a wild-card berth by 10 games.
Mattingly still has two more years left on his current deal with the Marlins, but the team's change in ownership raised some doubt about whether he'd remain at the post.
Derek Jeter, who is among Miami's new owners, declined to offer a firm commitment as to whether Mattingly would return when asked about the manager in October.
"It has been a long season," Jeter told reporters. "I told him to get out of here and go enjoy himself and get back to his family. We'll sit down when the time is right and evaluate everyone."
Mattingly and Jeter played together during Jeter's rookie season with the New York Yankees in 1995.
While Mattingly's return resolves one question, plenty of intrigue surrounds the Marlins, especially regarding slugger Giancarlo Stanton.
Jackson reported in September the new owners may trim the team's payroll, which would make Stanton a prime trade candidate. Stanton will earn $77 million over the next three years before he can opt out of his contract. FanRag Sports' Jon Heyman reported the St. Louis Cardinals are emerging as strong contenders to land Stanton, with the Philadelphia Phillies and San Francisco Giants also in the race.