On the field, Rodney McLeod is the last line of defense.

The Eagles' safety has one job. And that's to get between anyone with the football and the goal line. He's remarkably effective, and currently leads the team in solo tackles.

The unsung hero's arrival in Philadelphia this year, via free agency, is one of the main reasons (along with Malcolm Jenkins) the Eagles have a much-improved defensive backfield.

Now McLeod aims to carry some of that power and mojo off the field, where he's working to block cancer from taking any more lives.

The Eagles standout has been named an official ambassador for the Philadelphia-based American Association for Cancer Research (AACR), the largest scientific organization in the world dedicated to battling the disease.

"I'm hoping to draw more awareness, donations, anything that can help provide researchers with more money," McLeod said. "I naturally gravitated toward them."

McLeod's grandmother, Katherine D. Graham, succumbed to pancreatic cancer while still in her 50s. Her passing, during his senior year at DeMatha Catholic in Hyattsville, Md., left the powerhouse defensive back devastated.

"She was like my second mother," McLeod said. "She did everything for me."

McLeod called her NaNa. He was with her at the hospital when doctors performed the initial tests. Two days later, he was stunned to learn that the diagnosis was a virtual death sentence.

Pancreatic cancer is the among the most lethal of all cancers. There is no early screening method and it is ferociously difficult to treat. Ninety-four percent of diagnosed patients die within five years. (World Pancreatic Cancer Day will be observed Nov. 17)

During spare moments between school and sports, McLeod visited his NaNa in her hospital room.

"It was hard for me, hard to see her in that state," he said. "She was struggling, fighting for her life."

After her death in 2008, McLeod resolved to do whatever he could to help find a cause — and a cure — for pancreatic cancer.

"I'm trying to do my part to eliminate a disease that's extraordinarily painful," he said.

Before every game, right after the National Anthem, the 26-year-old McLeod pays a private tribute to his grandmother. He points to the NaNa tattoo emblazoned on the inside of his right bicep. Then he points to the sky.

"It's in remembrance of her," he said.

Cancer can run in families, but McLeod isn't worried.

"It's not how I live my life. I don't live in fear of anything," he said.

"My health, ultimately, is not in my hands. I believe God controls everything. My grandmother did, too," he said. "She was saved and I know she's in heaven looking over me."

As an ambassador for the American Association for Cancer Research, McLeod has launched fundraisers and planned several events with the proceeds going to study cancer.

On Monday, an auction closed on the hot pink cleats he wore against the Detroit Lions during the NFL's Oct. 9 breast cancer awareness effort.

On Nov. 29, Giving Tuesday, McLeod will spearhead an online campaign for the AACR.

"This is for people who have gone through what I've gone through, people who have cancer and their families," he said.

"While I'm in Philadelphia, I will do anything I can for them."

Contact Sam Wood at samwood@phillynews.com, 215-854-2796, or @samwoodiii

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