The window of Chase Blackburn's football career was about to shut. After six seasons as a Giant, the linebacker went unsigned as an unrestricted free agent during the offseason. He had a Super Bowl title to his name and had surpassed the average career of an NFL player by two and half years. He could retire a satisfied man.

The Bengals, Rams and Lions invited Blackburn to tryouts early in the season, but none signed him. "I know my workouts were for injuries that could occur or for maybe next year for camp," Blackburn said Sunday after playing a huge role in the Giants' 21-17 over the Patriots in Super Bowl XLVI. "They were trying to get a look at me and I knew that was what I was kind of going into. I tried to do my best and put it out there for them and hoped for an opportunity to play."

Left at home in Dublin, Ohio, with a wife and two young boys, Blackburn began planning life after football. He talked with a local middle school principal, one of his old football coaches, about a possible job as a substitute math teacher.

Then a familiar number appeared on his caller ID: Giants Stadium. It was Giants assistant general manager Kevin Abrams on Nov. 29. Injuries had left the Giants short at linebacker, and the organization needed to make changes one day after a 49-24 thrashing to the Saints. Blackburn got on a plane to New York and signed within hours.

Flash-forward to Sunday night. Blackburn was again on the biggest stage in the football world, with the whole globe watching him, rather than 25 eighth-graders.

On this night, he was the unsung hero, making the momentum-shifting play, two plays into the fourth quarter.

With the Patriots driving at their own 43-yard line and leading 17-12, Tom Brady unleashed a deep ball at Rob Gronkowski in the red zone. Blackburn, a linebacker, dropped downfield in coverage with the tight end and picked off the pass.

"That was a huge, huge turning point for us," defensive coordinator Perry Fewell said.

Speaking of turning points, the Giants were 6-5 before signing Blackburn. They are 7-2 since.

His teammates praise his value.

"He's one of the biggest parts why we're here," cornerback Aaron Ross said. "As soon as he came in, he put together the total package for us. We were missing that middle linebacker: A guy that could come in and have experience and he came in and did a tremendous job for us."

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"He made a lot of big plays," safety Antrel Rolle said. "He's been doing that ever since he stepped into Giants gear. We couldn't have done this without Chase. That speaks volumes for what kind of guy he is. His character and most of all, who he is as a teammate."

Beyond his performance on the field, his teammates cannot respect Blackburn enough for the mental toughness and work ethic he exhibited to make his comeback.

"He's done a great job," offensive tackle Kareem McKenzie said. "It's one of those situations where a guy had an unbelievable work ethic to start with and kept himself in shape and came back and made significant contributions to this team. You can't discredit the work ethic that he put into it to make sure he came in here, was able to contribute to this team in any, way, shape or form and to go ahead and play week in and week out."

"I love him," fellow linebacker Michael Boley said. "Chase is amazing. To go from where he was, weeks ago, you know, first half of the season not even getting picked up by anybody. Just being at home, for him, I love his attitude. The way he stayed focused, kept working out, kept his body in shape and he came back and was just an amazing player for us."

"Chase hung in there from Week 1," said running back Brandon Jacobs. "He hung in there, he stayed strong, he worked out. His opportunity came. He took advantage of his opportunity. He came up big for our defense. He got in there and made a lot of plays. I take my hat off to Chase. He came in and did when no one thought he could."

Blackburn does not have any hard feelings for the Giants waiting to re-sign him. He only appreciates the present.

"This feels incredible," he said. "Guys never would have planned for this, for me, myself, our teammates and my coaches and everyone in this organization. Obviously when the season started, halfway point in the season, I still wasn't here, so it's a blessing to be where I am today."

Blackburn's opportunity in 2011 started a bit past the halfway point in the season, with an appearance against the 11-0 Green Bay Packers. He wasted no time in pronouncing his return, making an interception in the second quarter.

"He's a fighter," linebacker Mathias Kiwanuka said. "He was on the couch for eight, ten weeks, something like that and he came in, stepped in, and had an interception his first game, so that shows you what kind of determination he has, and I was saying earlier, he's about as prototypical as a New York Giants defensive player can be because no matter what's thrown at him, he just continues to fight."

"Chase Blackburn, man, you can't say enough about him," Fewell said. "He comes one week, in Green Bay, he lines up, he gets an interception against Green Bay, he plays in the biggest game of our season, the Super Bowl, and he makes a big play there. You can't say enough good things about him."

For Kiwanuka, there is still a bit of frustration the Giants did not have Blackburn on the roster from the 2011 get-go.

"I mean, the guy, he's always been a phenomenal player,” Kiwanuka said. "He was our special teams captain last year, which is something that people forget. He knows exactly where he's supposed to be at all times. He can get people lined up in a heartbeat. He takes information from the meeting room to the playing field better than any guy I've ever seen in my life and he fights. He continues to fight."

For Blackburn, there was no frustration Sunday night. Just over two months ago, he was rushing to get workouts done while his kids were napping. Today he is a New York hero and once again, a Super Bowl champion.

But there is bad news. It came from the principal.

"He just texted me a couple days ago," Blackburn said. “The teacher that was going on maternity leave that I would have been substituting for just went into labor and had the baby this weekend, so I would start on Monday. I said, 'Why does school start on Monday. It's Super Bowl Sunday.' I was completely joking."

He may be kidding, but that class better find a substitute teacher. Blackburn has a parade in New York prepare for. He has cemented his place in the Canyon of Heroes.

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