EAST RUTHERFORD, N.J. - It was almost five years ago that Mark Herzlich was an undrafted free agent. The Conestoga High product had already beaten cancer. Now he was trying to reach the NFL. Herzlich turned down an offer to play in a minor league, choosing instead to bide his time until an NFL franchise called.

And he got his chance in July of 2011 when the New York Giants invited him to training camp. Herzlich, who starred at Boston College, made the most of it. He made the Giants that summer and has never left. The undrafted player has proven to be a mainstay with the Giants thanks to his versatility and work ethic.

The 6-foot-4, 246-pounder first solidified himself as a key special teams player, but now he's proving he can stick at linebacker. Herzlich was plugged last week into the strongside linebacker spot due to an injury to Devon Kennard. Herzlich racked up six tackles, proving to be an efficient run stopper. He can play all three linebacker positions.

Kennard has not practiced this week, meaning that all signs point to the 28-year-old Herzlich starting on Monday night against the Eagles.

"A lot of it for me is 100 percent hustle on every play," Herzlich said. "Trying to refine the talents and skills that maybe I'm weaker at, but using the things that I am good at and doing it on every play. I take pride in the leadership that I have on this team."

Herzlich was diagnosed in May of 2009 with Ewing's Sarcoma, a rare form of bone cancer. Boston College's defensive leader - and the conference's defensive player of the year - would miss the 2009 season as he went through chemotherapy.

Herzlich prayed each morning and night for two things: to be cancer free and to play football again. His prayers were constant, Herzlich said. Football was his motivation. Herzlich would watch his highlight tape as he sat in a doctor's waiting room. If he could play football again, then that meant his cancer was gone.

Herzlich was declared cancer free on Oct. 3, 2009. He played for Boston College on Sept. 4, 2010.

"The fact that both of those came to fruition is incredible," Herzlich said. "As far away as I get from that cancer diagnosis and being cancer free, more people distance me from it. But I try to tag that onto my name still, in order to give people hope and in order to reach out to people that are fighting now."

mbreen@phillynews.com

@matt_breen