Early in his career Johnson was the star of the Pats defense. While Bruschi was running around on special teams, it was Johnson who was corralling running backs like Jerome Bettis. He then had to go through some terrible injuries and a reduced role. Last year, however, he seemed to be as good as ever and was an integral part of the Patriots Super Bowl Championship.
Tom E. Curran of the Providence Journal wrote a good article (firstname.lastname@example.org, password: dandan -- thanks to bugmenot.com) summing up Johnson's career and going through some scary details about Johnson's concussions:
...Johnson cited symptoms such as irritability, cognitive clarity, trouble sleeping and memory loss as things he's experienced. "It was strongly urged and suggested that I should consider the ramifications (of continuing my career)," he added. "Could I still play? I could still play, but I open myself up to some potentially damaging long-term health issues. I love this game. But at the end of the day when I look at my wife and kids, those are the most important things to me."
Asked how many diagnosed concussions he's had, Johnson could only guess that it was around six. But he didn't include times that he was on the field and "couldn't focus, when it felt like my head was still moving. It happened more than it should have and I maybe let it go and maybe didn't say anything. It happened more frequently than I care to remember, quite honestly." So on the day he was to report for his 11th season, Johnson instead called it a career.Also in the article, Bill Belichick summed up the Johnson retirement very well: "It goes without saying, but Ted Johnson is a class act. He was a solid contributor to this defense and the New England Patriots organization his entire career. Ted's signature was a work ethic and toughness that were second to none. He retires a champion."