The Buffalo Bills, Oakland Raiders and New York Giants have had discussions about trading for Arizona Cardinals quarterback Matt Leinart, league sources tell ESPN NFL Insider Adam Schefter.

Leinart and the Cardinals are tiring of each other and as each day passes, many believe a trade of Leinart, who is unhappy that he's not starting, is more likely with roster moves coming this weekend, sources said.

And one executive told ESPN.com's Mike Sando that the Cardinals were calling around, trying to gauge the market for Leinart.

Cardinals coach Ken Whisenhunt has decided to start Derek Anderson instead of Leinart in Thursday's preseason finale -- the second straight game Whisenhunt has tabbed Anderson as the starter instead of Leinart, who was widely expected to claim the job following Kurt Warner's retirement.

That decision followed a meeting between Leinart and Whisenhunt Monday afternoon, after the former Heisman Trophy winner told reporters that he had outplayed Anderson in training camp and preseason, and that his problem with his coach "probably goes beyond football."

The Bills' website said the team has not discussed trading for Leinart and will not trade for him. But two sources said the Bills had ongoing discussions this summer with the Cardinals regarding a trade for Leinart.

Bills offensive coordinator Curtis Modkins coached Arizona's running backs last year. He is a big Leinart proponent and explained to Bills officials why he believed the team should make a trade for Leinart, a league source said.

Buffalo, however, is unlikely to trade for Leinart because the Bills are uncomfortable about bringing aboard the quarterback's contract, which carries a $2.485 million base salary this season and balloons to $7.36 million next season.

As for the Raiders and Giants, at least one member of each organization had a conversation this week discussing the idea of trading for Leinart. It is unknown how serious each team is about Leinart, but the topic has been broached in the organizations. The point to all this is clear: The Cardinals are willing to deal Leinart.

The Raiders denied interest in Leinart on Wednesday, saying in a statement they have never discussed acquiring him and that they are "very happy" about their quarterback situation.