On Monday morning, FoxSports.com's Jon Morosi tweeted that the Mariners and the Diamondbacks have spoken with the Tigers about a package to acquire Porcello.
And the Tigers are listening to all possible suitors.
Morosi went into more detail later on Monday, releasing a story with the details of the possible trade options, reporting the Tigers would ask for a shortstop, reliever or right-handed outfielder in return for Porcello.
The Tigers have publicly shown a lot of interest in acquiring Baltimore Orioles shortstop J.J. Hardy, and may have considered including Jhonny Peralta in a deal to acquire Hardy.
Morosi took to Twitter again late Monday night, reporting that the Orioles are no longer interested in discussing a trade involving Hardy, but revealed in a story that Baltimore is contemplating shipping closer Jim Johnson to Detroit in exchange for Porcello.
The addition of Johnson might be attractive for the Tigers just in case rookie Bruce Rondon doesn't pan out as the team's new closer.
Johnson, a 29-year-old, right-handed veteran, led the Major Leagues with 51 saves last season and turned in a sizzling 2.49 ERA.
The seventh-year pitcher has spent his entire career with the Orioles and has a lifetime ERA of 3.14.
Porcello, whom Morosi called the best fifth starter in baseball, went 10-12 with a 4.59 ERA last season and hasn't improved over four-year MLB career.
His best year was as a rookie in 2009, when he went 14-9 with a 3.96 ERA in 31 starts. Since then, he's failed to post an ERA under 4.00, and has a record of 34-33 in the last three seasons.
The Tigers haven't been shy about shopping Porcello—who won't be a free agent until 2015—and will have plenty of firepower in the starting rotation next season.
The Tigers signed Anibal Sanchez to a five-year, $80 million contract, and along with Justin Verlander, Max Scherzer and Doug Fister, Detroit expects Drew Smyly to figure into the rotation, which would leave Porcello on the outside looking in.