Jones promoted offensive coordinator Jason Garrett to interim coach. Defensive line coach Paul Pasqualoni replaces Phillips as defensive coordinator.
"Obviously this is a very difficult decision for me, our team, our organization," Jones said at the Cowboys' Valley Ranch headquarters. "We're clearly not where we want to be. That's an understatement. We also share the responsibility in that, all of us. An in-season coaching change is something that I have not done before (in 22 seasons as owner), something that I was reluctant to consider as late as ... Saturday night. ... There was a lot of me in denial. ... But at this time, what's in the best interest of the organization and the fans is a coaching change.
"I recently addressed the team. I told them that they should not think for even a second that this is in any way an admission of defeat or finality for this season ... that the evaluation process will begin with finding the guys that play the hardest. I told 'em we were looking for players that want to win the most. ... We are not recognizing the need to play in a winning way."
Jones, who co-captained Arkansas' 1964 national champions, has been particularly bothered by the apparent lack of effort in recent games, particularly on defense. The Cowboys, who allowed the NFL's second-fewest points, 250, while winning a second NFC East title in three years in 2009, surrendered 121 points the past three weeks.
"I know how fleeting your time is to get to play," Jones said. "You oughta play like it's the last play of your life every down. I don't think we're having that. ... Eight games is a lifetime in football."
Jones said that the 44-year-old Garrett was the right choice even though he has never been a head coach because over the past three years he directed the most prolific offense of Dallas' superb 51-year history. If the Cowboys produce what Jones called "tangible" results, Garrett might have the interim tag removed.
"I do believe that Jason has the disposition ... to affect a culture change," said Jones in an indirect shot at the genial Phillips. "His style is one that I think can be real effective. Culture change does work. I think this gives us a chance to do it from within. If we do outstanding as a team and have very visible, very tangible success then that's certainly doing your job in a crisis situation. That kind of action goes beyond a resume. Jason has some qualities of leadership, some qualities of organization. He's very smart. He's got some qualities that can get us where we want to go."
Garrett, who reportedly turned down the head coaching jobs in Atlanta and Baltimore in 2008 to remain in Dallas as a highly-paid coach-in-waiting, won't be in charge of repairing the defense. That falls to the 61-year-old Pasqualoni, who led Syracuse to nine bowl games in 14 years as its coach (1991-2004).
"I always felt that (Wade's) head coaching would have a great benefit from how well his defense is doing," Jones said about Phillips, who had coordinated successful defenses in San Diego, Buffalo, Denver and Atlanta before coming to Dallas. "When we started having the problems we're having over there, it compounded the overall team thing. We've got to get a defense that can slow 'em down.
"I might not be sitting here today if we had played well against Jacksonville and then we'd gone gone up at Green Bay and played lights out defensively."
Instead, it's lights out for the 63-year-old Phillips.
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