''In this business, if you're thinking about what was, you've got issues,'' Stafford said. ''I feel like I've trained my body and my mind for as long as I've played quarterback to forget the last play, forget the last game, whatever it was, good or bad, and go forward.''
If the second half of Detroit's playoff game at Dallas had gone a bit differently, the narrative surrounding Stafford might have changed considerably.
The Lions have won one postseason game in the past half-century, and in six seasons with the team, Stafford has been unable to add to that meager total. Detroit nearly broke through last season, but the Lions allowed the final 17 points in that 24-20 loss to the Cowboys.
There was, of course, that moment of controversy when officials reversed themselves, negating what at first looked like a crucial pass interference call against Dallas. That was particularly tough to take for the Lions and their fans.
Because Detroit lost, Stafford's performance in that game - 28 of 42 for 323 yards - has been largely forgotten. Instead, he enters this season still trying to prove that he is the quarterback who can lead the Lions deep into the postseason.
Last year was his first season under new coach Jim Caldwell, and his numbers were fairly pedestrian. He threw for 4,257 yards - the lowest full-season total of his career - with 22 touchdowns and 12 interceptions.
The Lions have done their best to put talent around him. Before last season, they added receiver Golden Tate. Now they've overhauled their offensive line and drafted running back Ameer Abdullah. And some more familiarity with the system could help.
''It's the second year in this thing,'' star receiver Calvin Johnson said at minicamp Thursday. ''His comfort level has risen a lot. I'm sure if you talked to him, he'd probably say the same thing.''
Stafford said there's no question the team is making strides this offseason. Detroit made the playoffs as a wild card last season, thanks in part to a terrific defense. With Ndamukong Suh having left via free agency, the Lions may need more from the offense.
Stafford measures up favorably - by a wide margin - against other recent Detroit quarterbacks. But as the No. 1 pick in the 2009 draft, the standard is higher for him.
Stafford's 2011 season - his only other playoff appearance - remains a bit of a benchmark. He completed 63.5 percent of his passes that season, throwing for 5,038 yards and 41 touchdowns.
His yardage has declined steadily since then, although he did complete 60.3 percent of his passes in 2014, his first time over 60 since 2011.
Stafford says he'll spend some time over the next five or six weeks thinking of some personal goals he'd like to reach this season.
''I have them, usually every year. Just things that maybe on paper you can quantify, maybe you can't,'' he said. ''I'll spend some time and think about that, and you'll probably ask me about it in training camp, and I won't tell you, and it'll be great.''
Although Caldwell is fine with players having personal goals - and he wants them to be lofty - he objects to the idea that the offense needs to be more flashy or put up huge numbers.
''We're more interested in winning games,'' Caldwell said. ''So, sometimes that requires an offense to take care of the ball and not give it away and be very, very effective. It has nothing to do with really scoring. We can play defense. We have a good defensive team and when you do that you have to play complementary football.''
In other words, the team's success or failure hinges on more than just its quarterback.
''I know a lot of people that like to kind of point and say, `Matthew's got to do this,''' Caldwell said. ''Matthew just has to do his job.''
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