Houston Texans tight end C.J. Fiedorowicz may see his career end early due to repeated concussions. 

According to a report from ESPN.com, Fiedorowicz -- who has sustained at least four concussions during the last two years, including three this season -- could be forced into retirement at the age of 26. 

Now, either by his choice or that of the Texans' doctors, Fiedorowicz might not be able to play again, sources said. He will have to pass a team physical, and there are no assurances at this point that he can do that. If he can't, his career could be over.

There was concern that Fiedorowicz could be forced into an early retirement even before he left last Sunday's loss to the Tennessee Titans with a concussion. When the Texans awarded him a three-year, $21.5 million contract extension last summer that included $10 million guaranteed, they included a de-escalator that would bring down his base salary by $2.8 million if he were to be cut as a result of a pre-existing condition such as a concussion.

The Texans drafted Fiedorowicz in the third round back in 2014 and over the course of several seasons, he emerged as the team's starter and one of its top passing game targets. He missed one game due to a concussion in 2016 and was limited to just five games this season due to his repeated head injuries.

Fiedorowicz would of course not be the first player to retire because of concussion concerns. Former 49ers linebacker Chris Borland retired from the NFL after just one season largely due to concerns about possible head injuries, Hussain Abdullah retired after seven seasons, and older players as far back as Troy Aikman and Steve Young suffered repeated concussions during their playing careers as well.