Three 49ers vets provide assistance to sign Bowman

Programming note -- log onto CSNBayArea.com today at 1:15 p.m. to watch head coach Jim Harbaugh address the media from 49ers headquarters.

The 49ers put together another team effort this week to sign All-Pro inside linebacker NaVorro Bowman to a contract extension through the 2018 season.Tight end Vernon Davis, cornerback Carlos Rogers and defensive lineman Ray McDonald restructured their contracts to provide the 49ers with the necessary cap room to award Bowman with a 7.5 million signing bonus, a league source told CSNBayArea.com on Friday.Bowman, whose original four-year deal averaged 623,062 annually through 2013, signed a five-year extension this week through 2018 that averages 8.911 million annually.Because of his signing bonus, Bowman's 2012 cap figure immediately rose from 717,887 to 2.217 million, the source said.In order to fit Bowman's new deal under their salary cap, the 49ers turned to three veterans to clear nearly 2.5 million in cap space.Davis provided the biggest cap relief for the 49ers of approximately 1.2 million. Davis' 2012 cap figure went from a little over 8 million to 6.8 million. The 49ers awarded Davis a 1.48 million signing bonus and had his remaining 25,000 per game active roster bonuses for the final five regular season games designated as an OATSB item (other amount treated as signing bonus).Rogers' salary figure went from 5.5 million to 4.7 million, as he also had his per-game roster bonuses for the final five games converted to OATSB. McDonald's cap figure went from 4.154 this season to 3.6 million, as his original 2013 base salary was partially converted to an option bonus.The overall framework of those contracts did not change. Davis' contract still averages 7.35 million through 2015; Rogers' average salary is 7.325 million through 2015; and McDonald's deal averages 4.02 million through 2015.The 49ers are currently 1.442 million under the league's salary cap.