One could surmise by the way the 49ers' secondary looked against the Tony Romo and the Dallas Cowboys that San Francisco could use some help at cornerback.Who was the best cornerback still available this week?The New England Patriots, who know a thing or two about talent evaluation, targeted Phillip Adams when they looked for help in their secondary.Adams, among the 49ers' final cuts, signed with the Patriots on Wednesday. Adams played in 15 games last season with the 49ers after the club selected him in the seventh round of the 2010 draft.In the next-to-last game of his rookie season, Adams sustained a broken ankle -- similar to Buster Posey's injury. Adams claimed he was 100 percent after returning punt 32 yards against the Raiders in an exhibition game. But the 49ers did not agree, and he was released.The 49ers kept five cornerbacks on their roster ahead of Adams: Carlos Rogers, Tarell Brown, Tramaine Brock, Chris Culliver and Shawntae Spencer. Adams does not have any practice-squad eligibility remaining.