By Shawn S. Lealos

The Dallas Cowboys opened the 2015 NFL season with high expectations. Their only major loss was when they let running back DeMarco Murray, the reigning Offensive Player of the Year, leave as a free agent for the Philadelphia Eagles. However, while many fans thought any running back could step in, things went from bad to worse when injuries to starting quarterback Tony Romo and Dez Bryant put the focus on the running game, and no one stepped up to take the lead. With the Cowboys on a bye week, the coaches are now toying with changes on the offense. Here is a look at team headlines throughout the bye week concerning injuries to the Cowboys.

Lance Dunbar Injury Opens Up Opportunity For Christine Michael

Through the first four games of the 2015 NFL season, neither starting running back Joseph Randle nor free agent pickup Darren McFadden could step up to replace Murray. However, one running back was tearing things up in the passing game as Lance Dunbar was one of the Cowboys’ top receivers thanks to the short passing game of Brandon Weeden. However, Dunbar tore his ACL and his season ended. After one week of watching Randle and McFadden continue to play uninspired football, Dallas looks ready to turn to Christine Michael, who they received from the Seattle Seahawks in a trade. “He’s bigger than the guys we have, he’s quick, he’s explosive,” Garrett said of Michael. And after the bye week, he might be the starter.

Matt Cassel Heads Into Starting Lineup

When Tony Romo went down with a collar bone injury in Week 2, Cowboys’ fans just hoped that Brandon Weeden could hold things down until Romo returned around Thanksgiving. However, after three straight losses, Romo’s injury is threatening the Cowboys season. As a result, Matt Cassel will step in to start for Dallas, with the team hoping he can open up a downfield passing game, something Weeden struggled with. “He’s started games in this league,” Garrett said of Cassel, “and he’s won games in this league.” Romo can return for the Miami game, the Sunday before Thanksgiving, but if Cassel can step up, they can maybe hold off until that Thanksgiving Day showdown with the Carolina Panthers.

When Will Dez Bryant Return

Before the Dallas Cowboys season turned south after Tony Romo’s injury, the team also lost Dez Bryant in Week 1 with a broken foot. Bryant promised he would return soon, some expected him to remain out until around Thanksgiving, and Roddy White of the Atlanta Falcons predicted that Bryant would not return this season at all. Bryant wants to return for the New York Giants game after the bye, but as Jason Garrett said, this isn’t about being tough. Dallas doesn’t want to lose Bryant longer by rushing him back too soon. “We’re getting there,” was all Bryant would say this week.

Randy Gregory Returns to Practice

When the Dallas Cowboys drafted Randy Gregory in the second round of the 2015 NFL Draft, he was considered the best pass rusher in the draft. In a perfect world, Gregory, DeMarcus Lawrence and Jeremy Mincey could rotate in and out alongside Greg Hardy and help improve the Cowboys rush defense. However, Hardy was suspended until last weekend and Gregory has been out since injuring his ankle in the season opener. Hardy returned last week and the Cowboys sacked Tom Brady five times in one half of play. Now, Gregory is back at practice and looks to play as soon as the Giants game after the bye week. Dallas’ defense is almost at full strength.

Shawn S. Lealos is a freelance writer who graduated from the University of Oklahoma in 2000 with a Bachelor’s Degree in Journalism. He writes for a variety of national publications and has over 15 years of sports journalism experience. Follow Shawn on Twitter @sslealos. Examiner.com.