That ruling came down on Thursday.
The league announced that Mansally was suspended for one game and fined an undisclosed amount for the headbutt that came during the 61st minute of RSL's 1-0 loss at RFK Stadium, and he will miss RSL's rivalry bout against the Colorado Rapids on Saturday night.
The Disciplinary Committee also fined Mansally's teammate Alvaro Saborio an undisclosed amount for his showing of "aggravated dissent" during second-half stoppage time of the same match.
In an incident in a separate game, Sporting Kansas City's display of "mass confrontation" (i.e. three or more players approaching a referee about a call or an opponent) in second-half stoppage time of Saturday's match against Toronto FC resulted in a warning from the Disciplinary Committee. As per new league policy this season, the next incident will result in fines for the club and coach Peter Vermes.