The D-backs confirmed that they have interest in acquiring the veteran left-hander, who was designated for assignment by the Tigers this weekend.
"We are at least considering him," D-backs general manager Josh Byrnes said Monday.
That was as far as Byrnes would go, except to say that he has had discussions with Detroit regarding Willis.
Willis, who was 1-2 with a 4.98 ERA in eight starts and one relief appearance for the Tigers this year, was signed to a three-year, $29 million contract extension by Detroit in 2007 not long after the Tigers acquired him from the Marlins.
Willis' rights are still controlled by the Tigers, who are on the hook for the rest of his salary. They could place him on waivers, and if a team claims him -- unlikely -- it would owe him the rest of his salary. If he were to clear waivers, he would be a free agent and the team signing him would only have to pay him a prorated portion of the minimum salary this year.
Right now, though, the D-backs are in discussions with Detroit over a possible trade.
Willis, 28, won a job in Detroit's rotation this spring and had quality starts in three of his first four outings. He struggled, though, in May, going 0-1 with a 6.52 ERA, and the Tigers elected to remove him from the roster to make room for Max Scherzer, who was recalled Sunday.
Command became a serious issue for Willis in 2008, and he spent much of the season on the disabled list with forearm and knee injuries. Last season, he started the year on the DL with what the club called an anxiety disorder.
"He was not happy," Willis' agent Matt Sosnick told MLB.com on Sunday night. "It was a really negative vibe for him. It's nothing that's Detroit's fault. It was a bad mesh."
The D-backs may very well be a better fit for Willis. Arizona is off to a poor start and had lost seven straight heading into Monday's series opener with the Dodgers.
Also, Arizona does not have a left-handed pitcher on its big league roster.
"It never worked out the way we would've liked it to work out," Tigers president/general manager Dave Dombrowski said when Willis was designated. "I don't think I really need to say any more than that. At the time, we thought we were getting a guy who would come in and be a very solid big league pitcher, and it didn't work out for us. Those things happen at times. You're never happy when they do. He's put forward the effort. We know we've dealt with a lot of issues with him. It's unfortunate."
Willis burst on the scene with the Marlins in 2003, when he went 14-6 with a 3.30 ERA for the World Series champions. Quick with a smile and possessor of a magnetic personality, Willis quickly became a fan favorite while winning the National League Rookie of the Year Award.
Willis' best season came in 2005, when he was 22-10 with a 2.63 ERA.
His fall from those heights and his control problems became a focal point during his time in Detroit. That is something Sosnick hopes can change with a new team.
"Wherever [Willis] goes next," Sosnick said, "I think he hopes he can be successful without him being the guy that has all these issues as opposed to being [another pitcher]. His playing games in Detroit was kind of secondary to figuring out why he wasn't the same guy who won the NL Rookie of the Year. Every time he pitched well, it was [a story of] the guy who was pitching well in spite of all the stuff he was dealing with. That's not to say it was anybody's fault, because it wasn't."