BALTIMORE (WJZ) — Ravens offensive lineman John Urschel is retiring from football, the team announced today.

“This morning John Urschel informed me of his decision to retire from football,” head coach John Harbaugh said in a statement. “We respect John and respect his decision. We appreciate his efforts over the past three years and wish him all the best in his future endeavors.”

READ MORE: FDA, CDC Recommend ‘Pause’ For Johnson & Johnson COVID-19 Vaccine Over Clot Reports

Urschel, a fifth-round pick in 2014 out of Penn State, is also a competitive chess player and is pursuing a Ph.D at Massachusetts Institute of Technology. He has published multiple peer-reviewed mathematics papers.

He released his own statement about his retirement from the NFL Thursday afternoon, in which he said he looks forward to working on his doctorate full time and spending time with his fiancee.

Retiring after just a few years in the NFL due to fear of brain injury is becoming increasingly common.

READ MORE: Maryland Directs All Vaccine Providers To Pause Johnson & Johnson Shot In Light Of Clot Reports

Just this week, a new study on chronic traumatic encephalopathy, or CTE, revealed that the degenerative brain disease is found in nearly 90 percent of all football players.

Researchers looked at the brains of 202 former football players, and CTE was diagnosed in 177 of them.

That includes 110 of 111 brains from former NFL players; 48 of 53 college players; nine of 14 semi-professional players, seven of eight Canadian Football league players and three of 14 high school players.

MORE NEWS: 16-Year-Old Armed With Airsoft Gun, Knife Killed In Trooper-Involved Shooting, Maryland State Police Say

Follow @CBSBaltimore on Twitter and like WJZ-TV | CBS Baltimore on Facebook