The Dolphins' Lamar Miller and 49ers' Frank Gore both got the start at running back in Week 1, but their backups performed more effectively than they did. Could their jobs be in danger as the season progresses, or even as early as Week 2?

The Dolphins and 49ers both won their Week 1 matchups on Sunday and rushed the ball very well. Perhaps so well that the coaching staff might have to make a decision, whether over the short-term or long-term, to incorporate some newcomer running backs. The Dolphins free agent signing of former Denver Bronco Knowshon Moreno and the 49ers second round selection of Ohio State running back Carlos Hyde may have each team's coaching staff contemplating their options.

In their 33-20 victory over the New England Patriots, Miller was the starting running back for the Dolphins. However, he received less snaps (27) than Moreno (48) and rushed for fewer yards and received much fewer carries. Moreno carried the ball 24 times for 134 yards and a touchdown compared to Millers 11 carries for 59 yards and a fumble. Miller also had four receptions for 19 yards and a touchdown to help his cause, but who will head coach Joe Philbin choose as the starter for Sunday against the Buffalo Bills?

"The question about who takes the first snap, now it's on my mind, but I hadn't considered it really yet," said Dolphins' offensive coordinator Bill Lazor, in this Miami Herald article. "I expect them both to contribute. There might be days (where) sometimes they may rotate by series and sometimes they may rotate by play if there are particular things they want. Some of it is going to be luck of the draw and the flow of the game. If a guy, if it's his turn to play and he runs for three first downs in a row, he's going to get to play more. They also get to earn some of it."

As for the 49ers, they beat down on the Cowboys pretty badly on Sunday. The score was just 28-17, but San Francisco led 28-3 at halftime and forced four turnovers while Dallas padded most of their stats in the second half while attempting a hopeless comeback. San Francisco rushed for 127 yards on the day, including 16 carries for 66 yards from Gore and seven carries for 50 yards and a touchdown from Hyde. The rookie received a solid amount of action in the preseason and mightily impressed the coaching staff, and Gore is in the final year of his contract. Will Hyde continue to eat into Gore's workload as the team moves on from the 10-year veteran?

Tune in to Sunday Night Football on NBC this week to see how San Francisco decides to play their running backs against the Chicago Bears.