The Scotland internationalist was sent off by Welsh referee Ian Davies in the 65th minute of the match for a dangerous swinging arm tackle on Dave Heffernan.
The player has a right to appeal but, as things stand, Swinson will miss Sunday’s European Champions Cup quarter-final at Saracens. He would also be out for the Warriors’ Pro12 games away to Munster, home to Zebre and also the Champions Cup semi-final on the weekend of 22/23 April should Glasgow progress.
The Disciplinary Panel in Neath, comprised of Simon Thomas (Chair), Richard Cole & Nigel Williams (all Wales), found that the referee’s decision to show the player a red card was not in error. The foul play merited a mid-range entry point point which carries a suspension of six weeks.
The panel’s statement said: “There were no off field aggravating factors but after considering mitigating factors, the committee reduced the final suspension to four weeks. The ban was therefore reduced by two weeks leaving the player free to resume playing on Monday, April 24, 2017. He was reminded of his right to appeal.”