Fairley told reporters Tuesday the team informed him this offseason that it was not picking up the 2015 option in his contract.
''It motivates me,'' he said.
Fairley recalled working out in Houston when Lions general manager Martin Mayhew called him about the decision on the $5.5 million option for the fifth year of his contract.
''It kind of surprised me,'' Fairley recalled.
Fairley said after calling his agent and having dinner with him, his mind was changed because he can get a new contract.
''We kind of came to agreement that it was good for both sides,'' he said.
Detroit drafted Fairley out of Auburn with the No. 13 overall pick in 2011 and he has struggled to sustain success in part because of his fluctuating weight. Fairley acknowledged playing too heavy last season while weighing as much as 320 pounds.
''I didn't feel comfortable with myself, my body, and how I was getting tired,'' he recalled. ''I just felt like if I got down to a lighter weight, I would be leaner, meaner and ready to go.''
Fairley said he has lost about 30 pounds, getting down to about 290 pounds. He started eating more baked chicken and grilled fish, cutting out his habit of eating fast food three days a week.
''He looks good,'' defensive coordinator Teryl Austin said. ''He's lost a lot of weight. I think the key will be when he leaves here and then when he comes back in camp if he's still in that great shape with his weight down. It's going to be great for us.''
Fairley was limited during Wednesday's practice because he is still recovering from surgery to treat sleep apnea, but expects to be ''full go,'' at next week's mandatory minicamp. He had career highs with six sacks and two fumble recoveries in 2013 while playing next to Ndamukong Suh, who is also entering the last year of his contract.
''We're just hoping that we get a big year out of (Fairley),'' Austin said. ''I think he wants to have a big year as well.''
Fairley was up for talking about a lot of topics and shied away from only one question, choosing his words carefully when a reporter asked him asked him about becoming a free agent after next season.
''We'll just have to wait and see,'' he said.
NOTES: NASCAR driver Joey Logano attended practice to promote next week's race at Michigan International Speedway. After the practice, he caught passes from and threw to the football to quarterback Matthew Stafford. Logano said drivers are like quarterbacks and a crew chief is like a coach, joking there would be only one place for his 6-foot-3, 175-pound body in football. ''I'd be on the bench,'' Logano said. ... The Lions will have a three-day mandatory minicamp next week before taking more than a month off before training camp begins.
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