The Football Association is to launch an investigation into the alleged spitting incident between Manchester United defender Jonny Evans and Newcastle striker Papiss Cisse.
Press Association Sport understands disciplinary chiefs are awaiting match referee Anthony Taylor's report while at the same time reviewing video footage from Wednesday night's game, which saw United win 1-0 at St James' Park.
The pair clashed after an Evans challenge on Cisse, with television replays suggesting both men had spat during an ugly confrontation.
Taylor is unlikely to have seen the confrontation as he followed play after waving away Cisse's initial appeals for a free-kick, although he was quick to intervene as tempers frayed once his attention was drawn to the fracas.
Both United boss Louis van Gaal and Newcastle head coach John Carver admitted they had not seen it in the immediate aftermath of the game, and the Dutchman said he could not imagine Evans spitting at an opponent.
The pair could face lengthy bans if charged and convicted, with then Hull striker George Boyd serving a three-match suspension last season for spitting at Manchester City keeper Joe Hart, a charge he denied.
A similar sanction could prove costly for both clubs, with United facing Arsenal in the FA Cup quarter-finals and Barclays Premier League top-four rivals Tottenham and Liverpool in the next few weeks, and Cisse Newcastle's leading goalscorer on 11 for the season.
It proved an eventful night on Tyneside, with the home side convinced they should have been awarded a 10th-minute penalty for Chris Smalling's trip on Emmanuel Riviere before Ashley Young snatched victory with an 90th-minute strike.
