Haley was hired as coach of the Kansas City Chiefs on Friday after helping the Cardinals reach the Super Bowl behind a high-powered offense.
Warner said the team needs to make sure it builds upon its success this season.
"I don't want to go backward as far as what we're doing, or having to readjust everything," Warner told The Associated Press following Pro Bowl practice Friday. "I want to be able to continue to move forward and to build off where we were this year. I think it's definitely going to be a factor in me weighing everything and making a decision."
While Warner said Haley's departure wouldn't be the main factor in whether he retires, it's another consideration.
"You have to look at the big picture," he said, "and wherever we're going and whoever is coming in, you just got to make sure you feel comfortable with that and they have the same mind-set. So at least from the football side of it, you feel comfortable that you can come back."
The situation will undeniably have some impact on continuity of the offense.
"It affects everything," Warner said. "Any time you make a change, and a major change, as you try to establish something, there's a lot of question marks there on what's going to happen moving forward."
Haley did not start calling plays until late in the 2007 season. But this season, the Arizona offense set a franchise record with 427 points, finished third in scoring in the NFL and was second in yards passing.
"He did a lot of great things for us: Bringing his knowledge of the game, shaping this offense, understanding all the pieces in place here and how to use them," Warner said.
Even receiver Anquan Boldin, who got into a sideline shouting match during the playoffs with Haley, had only positive things to say.
"He meant a lot to this team. He brought a lot to the table, especially on the offensive side of the ball. He'll definitely be missed in Arizona," Boldin said. "Everybody wishes him well and hopefully he'll get the job done in Kansas City."
Boldin said the departure is "definitely a blow" to the team.
"But it's the NFL. The coaches get jobs here and there. Players are moved here and there," he said. "One thing that happens is guys have to find a way to fill in. I'm pretty sure they'll get somebody to do that."
But perhaps no one worked as intimately with Haley than Warner.
"We worked very closely over the past two years to really build this thing the way we wanted it and shape the offense, and kind of design it around our playmakers and utilizing both our minds to do that," he said. "It's going to be different not having him around. But bottom line is I'm sure coach Whis (Ken Whisenhunt) is going to do a great job of bringing in a replacement and other guys are going to work together well."
Copyright 2009 by The Associated Press