Stendel lost two teeth, was left with blood pouring from his face after eye witnesses claimed former Burnley captain Barton HEADBUTTED and PUNCHED his rival manager in a tunnel bust-up, reports the Mirror.
Fleetwood boss Barton is at the centre of a police investigation with the authorities now taking statements from eye witnesses in the tunnel at Oakwell.
Police have already spoken to Barton and will speak to him again this week but have yet to take a statement from Stendel while he undergoes medical treatment. Charges may then follow.
Stendel did not speak to the media after the game but is expected to do a pre-match press conference on Wednesday ahead of his promotion-chasing team's next game with Shrewsbury on Good Friday.
Football League chief executive Shaun Harvey told the BBC: “As an off-the-field matter the tunnel is still in the domain of the referee but we will work closely with everybody to ensure it's not a case of who deals with the matter but actually the matter is dealt with properly.
“I was stunned when I heard. We have all heard of tunnel fracas as players have left the pitch. It's the first instance I've heard, described as it has been, by those who witnessed it.
“It's disappointing and it comes on the back of a number of challenges which have come to the surface for football to deal with. We need everyone who plays a part to lead by example."