© Mark J. Rebilas-USA TODAY Sports

When the Dallas Cowboys take the field against the Kansas City Chiefs on Sunday afternoon, all eyes will be on Dak Prescott and Patrick Mahomes. It's what will happen in front of the former that might raise some eyebrows though, with the Cowboys looking to make a change on their offensive line they hope will give them a better chance at stealing a victory at Arrowhead Stadium. Connor Williams, the team's resident starter at left guard, will be replaced by Connor McGovern, a talented former third-round pick who has been quietly improving in the background; and in a game that will likely see the return of All-Pro left tackle Tyron Smith.

The swap at left guard is a significant development for the Cowboys, and particularly for Williams, who is playing in the final year of his rookie deal and entered the 2021 season hoping to increase his value in Dallas. Instead, Williams was forced into a preseason experiment at center that was a complete failure before being moved back to left guard -- playing mostly well to this point. 

His Achilles heel, however, has been penalties that have routinely either killed drives and/or put the Cowboys offense in position to nearly lose critical games (e.g., in Week 6 against the New England Patriots). To date, Williams has been flagged for 10 penalties for a total of 110 yards, league high numbers in both categories, eight of them being holding calls. For contrast, his 10 flags are more than twice as much as center Tyler Biadasz (4), who is in only his second NFL season and four more than Terence Steele (6), who is also in only his second year and despite having been thrust into the starting role at right tackle during the five-game suspension of La'el Collins.

In other words, whether the penalties are all actual or not (spoiler: some aren't), Williams has put himself in the bad graces of head coach Mike McCarthy, and now he'll be benched because of it. McCarthy did note that both McGovern and Williams would play against the Chiefs, but not in what capacity -- presumably getting some fullback work that belonged to McGovern before now -- stopping short of naming the starter in Week 11. 

The latter mystery was solved by owner Jerry Jones who, not minutes later to 105.3FM the Fan, named McGovern starter. 

"Yeah, [McGovern has] had a frankly great fall and he has really impressed," said Jones. "He certainly impressed his teammates and coaches. This is a great opportunity for him. And he will really, I think, the way he's playing -- I think it says it all. 

"I don't know when I can remember anybody as an offensive lineman getting the attention he's gotten as a lead blocker coming out of a special formation in the backfield. He's doing it, not just with bulk, but he's doing it with feet. He's doing it with athletic ability. All of that is just intriguing when you think about it when he gets down in a regular offensive line position. 

"I think he'll do well. He's earned it."

One year ago, McGovern found himself starting at right guard due to a rash of O-line injuries that forced Zack Martin out to right tackle, and the then-rookie played well enough to make a name for himself in McCarthy's inaugural season in Dallas. Having done well at right guard, the Cowboys began testing him weeks ago at left guard, sending a message to Williams in the process. It's clear they don't feel Williams got the message, at least not in the realm of avoiding penalties, and so they'll now give the nod to McGovern -- in what will be his 10th NFL start but only second of the 2021 season.

Should he perform well, it might be the swan song for Williams in Dallas, unless he's fine with being demoted (permanently?), a move that will significantly impact any potential contract talks in the offseason to come.