Here are some underrated X factors who could make an impact in Week 6:
X factor: OT Matt Light
Analysis: New England's three-time Pro Bowler will draw a tough matchup against the Dallas Cowboys. Light will see a lot of five-time Pro Bowl outside linebacker DeMarcus Ware, who has five sacks in four games. Patriots quarterback Tom Brady noted his concerns about Ware this week. Look for Brady to get rid of the football quickly to his receivers this week. If Light can help neutralize Ware coming off the edge, New England will have an easier time going vertical downfield.
X factor: WR Naaman Roosevelt
Analysis: Buffalo deep threat Donald Jones suffered a high-ankle sprain against the Philadelphia Eagles. Jones will be out for at least a month. That opens the door for Roosevelt. He played surprisingly well last week in relief of Jones and recorded five receptions for 41 yards. David Nelson moves outside, while Roosevelt takes the slot, which is an important position in Buffalo's spread offense. Roosevelt's production in the middle of the field will be key against the New York Giants (3-2).
X factor: RB Shonn Greene
Analysis: If "ground-and-pound" is truly back in New York, Greene has to continue to raise his production. Green had his best game of the season in the Week 5 loss to New England, rushing for 83 yards and a touchdown on 21 carries. New York's offensive line has struggled, but Greene hasn't helped, either. He hasn't broken many tackles this season and his longest rush is for 15 yards. Jets coach Rex Ryan is adamant about giving Greene and the running backs more opportunities to carry the offense. So expect Greene to see the ball a lot Monday against the Miami Dolphins.
X factor: WR Brandon Marshall
Analysis: Marshall, the Dolphins' best receiver, could do new quarterback Matt Moore a huge favor by having a solid game. Marshall's assignment will be tough. He will be matched up against Jets corners Darrelle Revis and Antonio Cromartie — a duo against whom very few receivers have success. But Marshall always is capable of making big plays; if he gets a few against the Jets, Miami has a chance for the upset.