During the closing stages of the Championship fixture on September 22, Osmajic and Beck both played their part in a mass brawl between the two North-West sides.
Tensions boiled over after Beck had kicked out at Preston midfielder Duane Holmes, the left-back subsequently becoming the second player to be sent off at Deepdale after Sam Greenwood.
However, the major talking point came in the aftermath after replays showed that Osmajic had appeared to bite the Wales international on the back of the neck.
At the time, Beck remonstrated with the assistant referee, showing the bite marks, but the Montenegro international got away with a caution.
Nevertheless, retrospective punishment from the Football Association felt an inevitability once they had assessed the footage that was available.
How many games will Osmajic miss?
Osmajic was charged by the FA and it has since emerged that he pleaded guilty to biting Beck, the hope being that it may reduce his punishment.
Despite that plea, Osmjaic has been banned for Preston's next eight matches, as well as receiving a fine of £15,000.
The FA have also revealed that written reasons for the length of ban will be released in due course, Preston choosing not to officially respond to the development until then.
What matches will Osmajic miss?
Osmajic will not return to action until Preston's home Championship fixture against Derby County on November 23.
Seven of the eight games that Osmjaic will miss will come in the Championship, Paul Heckingbottom's side playing Burnley, Coventry City, Norwich City, Plymouth Argyle, Bristol City, Sunderland and Portsmouth during that period.
Furthermore, the 25-year-old will also be unavailable for the EFL Cup fourth round tie at home to Premier League giants Arsenal.
Preston will be without a player who has scored five goals in all competitions this season, two of them coming against Watford in midweek at a time when he and Preston were awaiting news on his punishment.