Rivera initially injured his back while running on a treadmill
in March 2005, only a week after signing his $20 million, five-year
free agent deal. He had surgery to repair a bulging disc in his
lower back, but still started the first 14 games in 2005 before
being sidelined by a strained neck.
Last season, Rivera started all 16 regular season games before
hurting his back again in the wildcard playoff loss at Seattle and
had surgery to repair a herniated disc.
When Rivera signed with the Cowboys, he was coming off his third
consecutive Pro Bowl season while blocking for Brett Favre in Green
Bay. Rivera played in 106 consecutive games for the Packers,
including seven playoff games, from 1998-2004.
Rivera was a sixth-round draft pick out of Penn State in 1996
but was inactive for every game that season when Green Bay won the
Super Bowl. He spent the next season primarily on special teams
before becoming a starter late in the 1998 season.
After getting hurt in 2005, Rivera offered to tear up his
Cowboys contract and return his $9 million signing bonus.
The Cowboys were already prepared for Rivera's departure, having
signed another big-money free agent this spring.
Leonard Davis signed a seven-year contract worth nearly $50
million with the Cowboys that included a $16 million signing bonus.
The 6-foot-6, 372-pound Davis spent the first six seasons of his
career in Arizona after being the No. 2 overall pick out of Texas