The 10-year veteran called the team with a change of heart after agreeing to a deal Tuesday night, Cowboys coach Jason Garrett said. Dallas is looking for an experience player at guard because of injuries to both of last year's starters, Nate Livings and Mackenzy Bernadeau.
"He decided when he woke up this morning that he didn't want to play football anymore," Garrett said. "So we respect that decision."
Dallas has been dealing with injuries at guard since training camp began more than two weeks ago.
Livings may not be ready for the season opener after undergoing arthroscopic surgery on his right knee for the second time in six months. He missed the start of camp with a cut on his foot. Bernadeau strained a hamstring in the pre-camp conditioning test and missed almost two weeks.
The 33-year-old Moore played 10 seasons for the Jets and started all 16 games for the last eight of those. He became infamous last Thanksgiving when Jets quarterback Mark Sanchez fell down and lost a fumble after running into Moore's backside in a 49-19 loss to New England.
Moore, who didn't immediately return a message from the AP, told ESPN he didn't want to leave his family for the cross-country trip to California. He had ties to Dallas through Cowboys offensive co-ordinator Bill Callahan, who was the Jets' line coach for four years before joining Dallas last season.
"What a tremendous player," Jets coach Rex Ryan said. "He was a great person, a great teammate, a guy that was important to me. Being a first-time NFL coach, I leaned on him some and he was absolutely tremendous. I guess you can't play this game forever, but I certainly appreciated the time he spent with us, for sure."
Cowboys owner Jerry Jones said the team was looking for a veteran at guard because they plan to start rookie Travis Frederick at centre and possibly another young player in second-year guard Ron Leary.
Dallas is still looking after Moore's decision, a sign the team is losing faith in Livings and Bernadeau just a year after signing both as free agents.
"I think the fact that they're limited, they've had injury, they've been out of camp, they were out of the preseason," Jones said. "I think that you could say yes that had something to do with it. That and the fact we're relatively young in there."
AP Sports Writer Dennis Waszak Jr. in Cortland, N.Y., contributed to this report.
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