With his junior year at Boston College over, Mark Herzlich was looking ahead to his final collegiate football season and then moving on to a professional career. The intense and sure-tackling outside linebacker was projected by many as a first-round NFL draft pick in 2010.

Then, on what was thought to be a routine visit to the University of Pennsylvania Medical Center to check pain and swelling in the left-thigh area, an MRI exam - and a follow-up visit to an oncologist - revealed that Herzlich had Ewing's sarcoma, a malignant tumor most often found in bone or soft tissue.

"That was a pretty emotional day, after meeting with the doctor and getting the diagnosis," said Herzlich, a former football and lacrosse standout at Conestoga High School in Berwyn. "A lot of things flashed through my head, like whether I'll be able to live a healthy life, my football career, and what my life will be like from here on out."

Herzlich, 21, started chemotherapy last Tuesday. His first treatment at Penn Medicine at Radnor lasted about five hours.

"Truthfully, I've had no side effects from it yet," he said. "No pain, no nausea or vomiting. I feel pretty good. That's encouraging, obviously. The key, though, is for me to take things one day at a time. I can't look too far into the future."

The 6-foot-4, 238-pound Herzlich is scheduled to go through eight weeks of chemotherapy.

In two months, he is expected to have surgery to remove the tumor, found in his femur. After a recovery period, there will be more chemotherapy.

"It's going to be a battle, for sure," Herzlich, of Wayne, said. "But I'm strong, ready for whatever it will take to get back to normal. I strived to be the best player I could be on the football field. I'm going to take the same approach, use the same work ethic with this. I'm confident that everything will be OK at the end of it."

At Boston College last season, Herzlich, who wears No. 94, registered a team best of 110 tackles, 81 of them solo; six interceptions, returning two for touchdowns; eight passes broken up; two forced fumbles; and two fumble recoveries. On New Year's Eve, he notched five tackles, two of them solo and two for losses, in the 24th-ranked Eagles' 16-14 loss to Vanderbilt in the Music City Bowl.

For his 2008 efforts, Herzlich was named the Atlantic Coast Conference's defensive player of the year. He was a finalist for the Butkus Award, presented annually to college football's top linebacker, and a quarterfinalist for the Lott Trophy, named after Ronnie Lott and given to the defensive impact player of the year. (Impact, in this usage, functions as an acronym for integrity, maturity, performance, academics, community, and tenacity.)

Herzlich's No. 1 support team is made up of his parents, Sandy and Barb, and 17-year-old brother, Brad. Brad Herzlich is a junior defensive midfielder for Conestoga's lacrosse team. In the PIAA District 1 Class AAAA playoffs, the Pioneers wore gold-colored laces on their spikes to show their support for Mark Herzlich in his fight against cancer.

"That was a nice thing for them to do," said Herzlich, who was on hand at West Chester Rustin High School for Conestoga's 10-4 quarterfinal win over Garnet Valley. "I was touched by that."

Fans, friends, teammates and coaches from Boston College are similarly concerned about his health. On the school's athletic Web site, bceagles.cstv.com., a message of encouragement for him can be posted.

One person, Dana from Waltham, Mass., wrote: "Mark, you are a true hero on and off the field. You have a fire deep inside unlike any other college football player. I know you will use that to fight and conquer this battle. We look forward to seeing you back on the field. Much love and encouragement. You are awesome!"

Said Eagles head coach Frank Spaziani, in a statement issued by the school: "When people think of Mark Herzlich, they think of a fearless individual who is always ready to take on a tough opponent. His integrity, determination and focus are unmatched. I know he will face this challenge with that same attitude."

Many others have reached out to Herzlich, including Notre Dame coach Charlie Weis; former Boston College teammate Matt Ryan, the Atlanta Falcons quarterback and the Associated Press' NFL offensive rookie of the year in 2008; and John Swofford, the ACC commissioner and Bowl Championship Series coordinator.

By telephone, Herzlich has talked several times to Weis, whose Irish bowed to Herzlich and the host Eagles, 17-0, in November. Herzlich had 11 tackles, 10 of them solo.

"He's been great," Herzlich said. "He said he had lit a prayer candle at the Grotto for me. He told me to stay positive and focused on getting better."

With Ryan, a 2003 Penn Charter graduate, Herzlich has exchanged phone calls and text messages. "We were good friends at BC," Herzlich said. "He said to me, 'You're a great guy, somebody that can beat this.' "

At Conestoga, Herzlich's contributions as a fullback and linebacker sparked the squad to Central League championships in 2004 and 2005. As a senior, he anchored one of the area's stingiest defenses and was a member of the Class AAAA first all-state team.

Joe Gallagher, head coach at Haverford High, a Central League rival, remembers a bone-rattling hit Herzlich made on running back Scott Lipschutz late in the 2005 season.

"Scottie was heading for the end zone," Gallagher said. "Mark came from the other side of the field and knocked him completely cold. Afterward, Scottie walked into the Conestoga huddle and one of our guys had to go get him."

Now, Herzlich's focus has switched to tackling cancer. "I can do this," he said. "My goal is get well and get back to playing football."

Contact staff writer Rick O'Brien at 610-313-8019 or robrien@phillynews.com.