New York Jets running back Braelon Allen is not available this week against the Dallas Cowboys with what head coach Aaron Glenn described as a “pretty serious” knee injury. Allen was injured on a kickoff return in the second quarter Monday night at Miami in the Jets’ 27-21 loss to the Dolphins. 3 in the NFL in rushing this season, averaging 144.5 yards per game and 5.2 yards per carry. The Cowboys allowed 123.3 rushing yards per game in the first month of the season. Allen, who lost a fumble at the 1 at Miami in Week 4, has 18 carries for 76 yards this season.