John Urschel drops football from his résumé to concentrate fully on math. (Steve Ruark/AP Images for Texas Instruments)

Something about playing professional football does not add up anymore for Baltimore Ravens offensive lineman John Urschel.

On Thursday, just two days after a new study revealed increasing evidence connecting the degenerative brain disease chronic traumatic encephalopathy to the highest levels of the game, the 26-year-old retired.

Baltimore, where Urschel played for three seasons, made the announcement online.

“This morning John Urschel informed me of this decision to retire from football,” 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.”

Urschel did not immediately comment on the news, but later posted a short statement on Twitter thanking everyone for the kind words.

“It wasn’t an easy decision, but I believe it was the right one for me,” he said, announcing he and his fiancee were expected their first child in December. “There’s not big story here, and I’d appreciate the right to privacy.”

Urshel, of course, already has a second career lined up, which he pointed to on Thursday. A doctoral candidate in mathematics at the Massachusetts Institute of Technology, Urschel has nine published or accepted research papers to his name, according to the school’s magazine MIT Technology Review. His specialties include discrete Schrödinger operators, high dimensional data compression, algebraic multigrid and Voronoi diagrams.

“I have never had a student like him,” Ludmil Zikatanov, who taught Urschel as an undergrad and master’s student at Penn State, told The Post’s Michael S. Rosenwald last year.

Urschel’s said in the past that he envisions a “bright career” for himself in mathematics. He’s also said, however, “I love hitting people.”

And although he did not mention it in his statement on Thursday, Urschel’s never been shy about talking about the possible risks to his brain from playing football. In fact, in a 2015 essay for the Players’ Tribune, he said he “envied” Chris Borland, who retired from the NFL at age 24 over concerns about CTE.

“Objectively, I shouldn’t [play football],” Urschel admitted in his essay. He added, though, that his passion for the game overrode the possible risks.

“There’s a rush you get when you go out on the field, lay everything on the line and physically dominate the player across from you,” he wrote. “This is a feeling I’m (for lack of a better word) addicted to, and I’m hard-pressed to find anywhere else.”

It’s unclear whether Urschel, who participated in all the team’s training sessions during the offseason, simply no longer feels that same passion, or if he now determined the risk to outweigh his love of the sport. (Or it could be something else entirely.)

If it’s the latter, however, it would hardly be a surprise following the release of a study this week conducted by researchers at Boston University School of Medicine and the VA Boston Healthcare System. Researchers studied the brains of 111 former NFL players who died in recent years and diagnosed 110 with CTE.

“Obviously, this doesn’t represent the prevalence in the general population, but the fact that we’ve been able to gather this high a number of cases in such a short period of time says that this disease is not uncommon,” neuropathologist Ann McKee told The Post’s Rick Maese this week. “In fact, I think it’s much more common than we currently realize. And more importantly, this is a problem in football that we need to address and we need to address now in order to bring some hope and optimism to football players.”

While Urschel is the youngest player to retire this week to continue to pursue his PhD, he’s not the only one. On Tuesday, 31-year-old wide receiver Andrew Hawkins, who had signed a one-year deal with the New England Patriots, ended his career, as well. He also pledged to donate his brain to CTE research in the future. In the meantime, Hawkins, who recently earned his masters from Columbia University, said he plans to pursue his doctorate in business and economics.

Read more about football and CTE:

Ex-NFL player doesn’t remember running through glass door. His wife thinks he has CTE.

‘My memory ain’t what it used to be’: Warren Sapp says he’ll donate his brain for CTE research

Aaron Hernandez’s brain to be donated to CTE study after DA confirms suicide

How a protein called ‘NFL’ could help the NFL with brain injuries