ACU's 3rd Series of Q4

Ball on NW 38.  Rush up middle to NW 33.  Richardson rushes to right for 3 to NW 30.  Richardson rush is short of 1st down.  Going or it on 4th and 1 with 5:15 left in Q4.  QB Stewart rushes to beat clock, passes out of bounds and is flagged for grounding.  First and 10 for NW at their 40.