By Andrew Porter

PHILADELPHIA (CBS) — Evan Mathis, who is unhappy with his contract situation, has been M.I.A during the Eagles’ voluntary offseason team activities this spring.

According to ProFootballTalk.com’s Mike Florio, Mathis was offered a raise, which was later pulled.

“A source with knowledge of the situation, Mathis contends that the Eagles previously offered to increase the salary paid to Mathis by roughly $1 million per year, from 2014 through 2016,” Florio wrote. “Mathis opted not to accept it in 2014, but he was interested in accepting it in 2015. But the Eagles, per the source, told Mathis that the offer was no longer available because Howie Roseman, who had made the offer, was no longer the General Manager.”

Mathis, 33, signed a five-year, $25.5 million extension in 2012. The two-time Pro Bowl guard is slated to earn a base salary of $5.5 million and $6 million, respectively, over the next two seasons in Philadelphia.

“We haven’t had an offer for Evan so there’s nothing to take,” Eagles coach Chip Kelly said back in May, when asked about trading Mathis. “Evan has been available for trade for two years now and we have never had an offer for him. That’s between his agent (Drew Rosenhaus) and him.”

On Tuesday, Kelly was again asked about Mathis’ situation and said, “We’re not going to discuss any players’ contracts. We never have, never will.”

Mathis’ teammate and fellow offensive lineman, Jason Kelce, discussed the situation on the 94WIP Morning Show two weeks ago.

“[Mathis is] locked in for another two years, so he doesn’t have a lot of leverage here,” Kelce explained. He wants more money and the team feels like they got him for a fair price and that’s where it’s at.”

Former Eagles president Joe Banner also weighed in on Mathis’ situation via Twitter, siding with his former franchise.