IRVING, Texas (AP) Kellen Moore faced Buffalo in the preseason when he was with Detroit, so Bills coach Rex Ryan already had an impression of the Dallas quarterback going into his first career start.
''First thing that jumps out at you, he's a little bitty dude,'' Ryan said. ''You're expecting these big 6-5 dudes and here's a guy that's 6-foot. Then he's throwing with the wrong hand.''
Ryan went on to say some of the same things others do about the left-handed Moore: accurate, poised, smart. But the first impression is always the same, and perhaps explains better than anything why Moore waited almost four years - most of that with the Lions - for his first regular-season snap in the NFL.
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The debut finally came in Dallas' 19-16 loss to the New York Jets last weekend, when Moore provided enough of a spark replacing the ineffective Matt Cassel to get the call Sunday at Buffalo. The Cowboys (4-10) and Bills (6-8) are out of playoff contention.
''Kind of used to the deal,'' said Moore, also generally described as lacking arm strength and speed. ''I'm not the biggest guy and kind of been that way for a while. I understand there are times I have to move in the pocket to see things. Some of us shorter guys find ways to get it done.''
Dallas offensive coordinator Scott Linehan was in Detroit in 2012 when the Lions signed the undrafted Moore out of Boise State, where he finished among career leaders in yards passing, touchdown throws and total offense.
Moore always got plenty of work in the preseason, but never in a game that counted. This year has probably been as good an illustration as any.
The 26-year-old joined the Dallas practice squad in September, before the first of Tony Romo's two broken left collarbones. When the first injury sidelined Romo for seven games, Moore was the backup to Brandon Weeden for two weeks while Cassel learned the offense following the trade that brought him from Buffalo.
Once Cassel was ready, Moore was bumped to third team. And just before Romo came back, the Cowboys put Moore on waivers and managed to get him back on the practice squad. Then came Romo's second injury, and Moore became Cassel's backup.
Coach Jason Garrett went to Moore in the second quarter against the Jets. Cassel threw an interception on a pass that was so far from any Dallas receiver that he got an intentional grounding penalty, and he was replaced the series after taking a 19-yard sack.
Moore threw an interception on his second career pass and had three overall, including one in the end zone with a chance to extend a 10-9 lead.
But he gave the Cowboys that lead by beating a blitz with a quick throw in the flat to Dez Bryant, and led a drive to a tying field goal in the final two minutes before the Jets went the other way for the win.
''I remember seeing him at the Senior Bowl and I remember the impression was only OK when throwing routes on air, better when he gets to one on ones, better when he gets to seven on seven, better when he gets to 11 on 11,'' Garrett said. ''And I think that's probably what his career has been all about.''
With Linehan running the offense, the Cowboys didn't take long grabbing Moore after he was released by the Lions at the end of the preseason.
''He knows what he can't do,'' Linehan said. ''His self-awareness is unbelievable. You look at some guys and say, `Well, he looks like a pro football player.' You might not say that if you walked through the halls and didn't know him.''
Moore never really stopped to consider whether that impression would keep from ever taking a snap in the regular season.
''I think you just kind of stay ready and that's the way you've got to approach it,'' he said. ''If that opportunity ever came, you've got to be ready. And fortunate for me, we have that here.''
The 1,318-day wait finally ended last weekend.
NOTES: Bryant missed practice Wednesday because of soreness in his surgically repaired right foot. ... WR Cole Beasley (illness) and CB Morris Claiborne (hamstring) also didn't practice.
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