Under the Texas Workers' Compensation Act, employers can have a predetermined list of network providers available for an injured employee to choose from for treatment. However, on occasions where an employer doesn't have such a list in their workers' comp policy. When this is the case, it's known as a non-network claim, and you're allowed to see any doctor you want that treats workman's compensation injuries.
Most employers do carry policies that have a specified network of medical providers you must choose from, though. These are considered network claims, and for your claim to be eligible, you will need to see a physician for treatment on their preferred provider list.