Dallas Cowboys guard Robert Jones sustained a broken bone in his neck and is expected to miss two to three months of action, a league source told UPI on Monday.

Robert Jones, who signed with the Cowboys as a free agent this offseason, broke a bone in his neck during practice on Sunday, according to ESPN, and is expected to miss 2-3 months.

Booker was the Cowboys' second-highest drafted offensive lineman in the common draft era, behind Tyron Smith in 2011, and he's one of three offensive linemen selected by Dallas with its last four first-round picks. He allowed two sacks on 979 career pass-blocking snaps in college, and will now have the chance to replace the legendary Zack Martin.