IRVING, Texas – The Cowboys’ coaches never did seem to figure out how to light a motivational fire under Martellus Bennett’s butt during his four disappointing seasons in Dallas.

Jason Garrett certainly isn’t about to do it now that the tight end, known for his wild personality and wasted potential, plays for the New York Giants.

Garrett had nothing but praise when asked about Bennett on Sunday, disagreeing with the premise of a question about why things didn’t work out for the Cowboys’ 2008 second-round pick in Dallas.

Garrett claimed that Bennett did what the Cowboys wanted him to do as the second tight end behind seven-time Pro Bowler Jason Witten. Garrett’s said Bennett performed “very well” in his primary roles as a run blocker and pass protector and did “a pretty good job” when he had opportunities in the passing game.

“The business of the NFL is that you can’t keep everybody when their contracts run out,” Garrett said. “We feel good about what Martellus did here. He’s going to go up to New York and do a nice job for them. He’s going to play a long time in this league.”

Let’s cut through the bull: You don’t draft a blocking tight end in the second round.

Give the Cowboys’ front office credit for not being complete fools, although they did draft a complementary back (Felix Jones) in the first round that year. They know you can find grunt-work tight ends, such as John Phillips, in the draft’s later rounds. They believed Marty B, with his size and athleticism, would be much more than that.

Valley Ranch folks raved about Bennett’s explosiveness early in his Cowboys tenure. They gushed about the way that he came out of breaks like a wide receiver. They dreamed of the possibilities while watching him make acrobatic catch after acrobatic catch in the Alamodome during the 2009 training camp.

But Bennett’s four-year totals would be one so-so season for Witten: 85 catches, 846 yards and four touchdowns. After teasing with four touchdowns as a rookie, Bennett failed to reach the end zone in the last three seasons.

The blame game for Bennett’s poor production in the passing game can be a chicken-or-the-egg kind of deal. Was it because he didn’t get enough opportunities? Or did he not get opportunities because he failed to earn the trust of the coaches and the quarterback?

We’ll find out this season.

We already know that Bennett was a wasted second-round pick for the Cowboys, whether or not Garrett wants to admit it a few days before facing the Giants.