10/09/2013 11:12 am ET Updated Oct 21, 2013

Drew Williams, Lane Tech Football Player Who Suffered Serious Head Injury, Improving

Updated story

The condition of a teen football star from Chicago's Lane Tech College Prep High School is slowly improving after he suffered a brain injury and collapsed during an Oct. 4 football game.

The Tribune reports the family of Drew Williams, 17, said Saturday the high school senior is no longer in critical condition, but the extent of his recovery is still unclear.

"Drew is no longer considered critical but still remains in a coma," Andrea Williams, Drew's sister, wrote in a statement "His life is no longer threatened by brain swelling."

Doctors determined Williams had suffered a subdural hematoma and later removed a part of his skull in an effort to reduce swelling in his brain during emergency surgery, Fox Chicago reports.

Friends and classmates of the star athlete have been writing tributes to Williams on a page and Williams' family is also accepting donations for his recovery fund via a page.

CPS CEO Barbara Byrd-Bennett has been in touch with Williams' family, according to ABC Chicago, and said in a statement "our thoughts are with the student and family during this difficult time."

Family friend Art Mora told NBC Chicago, "I'm still trying to wrap my mind around the whole thing. It's just surreal. Hopefully some sort of miracle happens. Drew can come back from this."

In 2011, PBS' Frontline aired a special on head injuries in high school football. According to the special, at least 60,000 concussions happen every year on high school football fields -- and even more athletes who don't report symptoms of a concussion suffer some degree of cognitive damage.