Chad Rinehart has been named the starter at right guard for Sunday's game against the Denver Broncos.
Rinehart replaces Will Montgomery in the lineup.
"We're going to start Chad Rinehart in place of Will Montgomery," Jim Zorn said on Friday. "And Will is going to be there backing up him and at center."
Rinehart, a 2008 third-round draft choice by the Redskins, started two games earlier this season but he was replaced first by Mike Williams and then Will Montgomery.
He hopes to show coaches he has improved enough to solidify the job.
"My last stint wasn't good enough to maintain the job, but I think it's just a matter of taking what I do in practice and bringing it on the field [on game days]," Rinehart said. "It's the same with the rest of the offensive line. We do well in practice but then when we get in the game we make mistakes. It's frustrating to see."
At 6-5 and 310 pounds, Rinehart is thought to add more size and strength to the interior offensive line than Montgomery, who is 6-3 and 305 pounds.
Montgomery also has significant value as a backup at two positions.
"Chad has done well and he has been fighting hard," Zorn said. "That's what has been great about that whole group. They all want to get on the field, it has just been a matter of how we felt about their practice time and what they can do."
Earlier this week, Zorn called the competition between Rinehart and Montgomery an "ongoing battle."
When Randy Thomas went down with a triceps injury in Week 2, it was Rinehart who won the starting job initially.
He started against Detroit and Tampa Bay in Weeks 3-4 but was suffered a shoulder injury.
Coaches turned to Mike Williams at right guard in Week 5.
Then Chris Samuels went down with a season-ending neck injury, forcing the Redskins to move Williams to right tackle.
Montgomery was chosen to start at right guard instead of Rinehart.
"I thought Will was doing a good job in there and now Rinehart is starting to come back on," Zorn said. "These guys are real competitive. I think Buges [Joe Bugel] is doing a very good job observing these guys every day.
"That is what we tell them every single day: it's not so much competition but it's being a pro. These guys are working hard doing that. Chad is starting to get better and better as we have gone through the last couple weeks."