The Marlins are "aggressively" looking to replace manager Ozzie Guillen, according to a Thursday tweet by Buster Olney.

Guillen's future with the Marlins has been in question over the past few weeks as the team finished a hugely disappointing season. The Marlins opened a new ballpark and added a host of expensive free agents last winter only to struggle.

"Will they wait to find someone before firing him?" Olney writes, "We'll see."