Arlington: Dallas Cowboys centre Travis Frederick has been diagnosed with a rare neurological disorder that causes weakness in various parts of the body, and the four-time Pro Bowl player isn’t sure on a timetable for a return.

Frederick said he has received two treatments for Guillain-Barre Syndrome over the past 48 hours and that the treatments will continue for several days.

“I am very optimistic about my condition and the immediate future, as I have been told that the illness was detected at a fairly early stage,” Frederick said. “My doctors have told me that it is not possible to determine a timetable for a return to the field right now, but I am hopeful that I will be able to play as soon as possible.”

The 27-year-old Frederick has started all 83 games, including three play-off games, since the Cowboys drafted him late in the first round in 2013. That streak is likely in jeopardy with the opener just over two weeks away, September 9 at Carolina.