Cowboys center Travis Frederick has been diagnosed with Guillain Barre syndrome, a rare auto immune disease, he announced on Twitter on Wednesday evening.
"My doctors have told me that it is not possible to determine a time table for a return to the field right now, but I am hopeful that I will be able to play as soon as possible," Frederick tweeted.
Frederick's injury had been undisclosed until he tweeted Wednesday evening, but he's been held out of practice and he didn't play in the Cowboys' preseason game on Saturday night.
Guillain-Barre syndrome is a rare condition in which the body's immune system attacks nerves, according to the Mayo Clinic. Symptoms include prickling sensations in fingers, toes and ankles; weakness in the legs that spreads to the upper body; rapid heart rate and difficulty breathing.
Frederick had been evaluated for what was believed to be a series of "stingers" during training camp.
Travis was optimistic about the diagnosis, tweeting, "the illness was detected at a fairly early stage."
"In the last 48 hours, I have received two treatments that address my condition," Frederick said, "and I am feeling much better from an overall strength perspective."
Frederick has been the anchor of the Cowboys' offensive line since the franchise drafted him in the first round in 2013. He was named first-team All-Pro in 2016 and second-team in 2014 and 2015. He's also a four-time Pro Bowler.