The two have rotated at the position the last two weeks with Free getting the majority of snaps in the fourth quarters of the last two games. It's expected to continue this week when the Cowboys face the New Orleans Saints.
When asked is it tough to rotate at right tackle, Free said, "Yeah, you can say that."
Free has started every Cowboys game since the 2010 season, a span of 46 games, so durability isn't an issue with him. What's at issue is how Free is handling sharing first-team snaps in practice and in games.
Offensive line coach Bill Callahan said Free has been professional and done a fantastic job in working with Parnell.
"You want to work with him and you want him to get better, that's what teammates do," Free said. "You want to help him the best you can."