As training camp neared, he elected against holding out. Mathis said he did not even like missing school as a child because he did not want to fall behind.
Mathis conceded the best leverage a player has is by holding out. He also admitted that he has even more leverage after Lane Johnson's four-game suspension, because the Eagles now have less offensive line depth.
"I'm not trying to strong-arm the team or put them in a bad situation to get what I want," Mathis said. "I'm trying to do the right thing."
Eagles safety Keelan Johnson was excused from training camp after Saturday's arrest in Tempe, Ariz. Johnson, who is entering his second season with the team, met with coach Chip Kelly on Thursday in Philadelphia.
There is no timetable for his absence. He will still count against the 90-man roster.
Johnson, 24, was arrested after Tempe authorities said he pushed a police officer following a bar brawl, according to various reports.
The Arizona State product joined the Eagles' practice squad at the beginning of last season. He spent 15 weeks on practice squad before being signed to the active roster on Dec. 17. Johnson finished the season with two tackles.
All 89 players besides Johnson reported to training camp on Friday.
The Eagles are nearing completion of their $125 million stadium renovation project. Lincoln Financial Field now includes 22,000 square feet of high-definition video boards. There is a new board behind each end zone and LED ribbon-board displays along each side of the stadium.
MATHIS SHOWS | GUARD WON'T HOLD OUT. D3