The Chicago Bears agreed to terms Thursday with former Oakland Raiders running back Michael Bush, and franchise back Matt Forte isn't happy about it.

Bush gets a four-year contract worth up to $14 million, including $7 million in guaranteed money, according to a source.

"There's only so many times a man that has done everything he's been asked to do can be disrespected!" read a post on Forte's Twitter account early Thursday afternoon. "Guess the GOOD GUYS do finish last ..."

Later in the day, Forte attempted to more succinctly direct his ire with the following two posts on his Twitter account: "for the record I'm not mad at the signing of another running back. This is 4th time that's happened. I embrace competition as well as help." He added, "But as for not taking care of ur own and undervaluing a player under his market value is another story! #twitterrant"

Forte recently was designated the club's franchise player as the sides work to come to a long-term deal. The signing of Bush could be viewed as somewhat of an insurance policy for the Bears in the event Forte decides to hold out. The sides have until July 16 to come to an agreement on a multiyear extension. After that date, Forte must play under the tag, which comes with a salary of $7.74 million.

"Since drafting Matt in 2008, the Bears have signed Kevin Jones, Chester Taylor and Marion Barber, all ostensibly to serve as Matt's backup," Forte's agent Adisa Bakari said. "To sign yet another running back, prior to completing a contract with Matt, suggests disregard for Matt and his contributions to the Bears."

Forte has said in the past that he would be "hard to find" if the Bears tagged him, but the Bears have been adamant in expressing a desire for the sides to come to a long-term agreement.

"Matt is going to play his football for the Chicago Bears, you start with that," coach Lovie Smith said at the NFL scouting combine. "In time, hopefully, we can get an agreement in place that suits Matt, and we feel comfortable with. I think it's just a matter of time. That will happen eventually."

Bush empathizes with Forte and said he figured his new teammate will hold out.

"I can understand where the guy's coming from," Bush said. "

Everything they've asked for, he's done. It's one of those things where you want to be rewarded for your success. I understand, but that has nothing to do with me. It'll be great working with him."

What the Bush deal most likely signals is the end for Barber, a 2011 free-agent acquisition, who carries a cap charge of $2.25 million into the 2012 season.

Releasing Barber would represent a cap savings of $2 million.

A fourth-round pick of the Raiders in 2007, Bush ran the ball 632 times for 2,642 yards and 21 touchdowns over four seasons, despite missing his rookie year because of a broken leg suffered in college at Louisville. Bush, 27, is coming off his best season as a pro, a campaign in which he gained 977 yards on 256 attempts in addition to scoring seven TDs.