News on an old Charger. http://sports.espn.go.com/nfl/news/story?id=2192107 FOXBOROUGH, Mass. -- New England Patriots safety Rodney Harrison tries to ignore the possibility that his career might be over, and is determined to return from a season-ending knee injury. "I cannot honestly say what's going to happen next year and what the future holds for me in terms of football," Harrison said Friday. "But I'm going to work my tail off to get back on the field." Harrison tore his anterior cruciate ligament, medial collateral ligament and posterior cruciate ligament during New England's 23-20 win over Pittsburgh last month. The Patriots placed him on injured reserve, ending his season. Harrison expects to undergo surgery in about a month, once the swelling in his knee subsides. Meanwhile, the 32-year-old safety is responding well to treatment and therapy. Harrison said he has always recovered from injuries faster than expected. "Now, as far as a timetable, do I know? No, I've never been injured like this before," he said. Harrison has started every game since signing a free agent contract with New England in 2003 after nine years with the San Diego Chargers. He was the Patriots' leading tackler the last two seasons and is the NFL's career leader in sacks by a defensive back. A rash of injuries has left the New England secondary in a "state of flux," and "hanging on by a really thin thread," but Harrison said he expects steady improvement as younger players get experience. "Once the secondary jells and they gain some confidence, I think we should be just fine," he said. Harrison is adjusting to his new role as a sideline mentor and observer. But he was home during last Sunday's game in Atlanta and found himself yelling so loudly at the television that his young son started to cry. "It's tough," Harrison said. "You wish you could go out there and do something. ... It really, really makes you appreciate the game when you're not around it."