The animosity is building ahead of Borussia Dortmund's Europa League knockout tie against Red Bull Salzburg, with the German club prohibiting the use of their logo on any match-specific merchandise.
You suspect that resourceful street vendors might find a way to knock out some cheap tat anyway, but there'll certainly be no official half-and-half scarves.
This has been coming. The relationship between Dortmund's supporters and Leipzig, another club under the energy drink umbrella, have been strained for a while and clashes between fans are reported whenever they meet.
This is an official stance, though, with the club's marketing director Carsten Cramer insisting that "we don't want any scarves where a promotional logo can be seen with ours".
It sounds petty, but it's really not: Dortmund's position seems to be that, having incorporated the logo into their badge, none of the Red Bull sides actually wear a proper crest. Fair enough, really.
See also...
Fenerbahce'sFernandaobanned after pelvic thrusting towards Besiktas fans
How Cologne have got through SEVEN different kits in the Bundesliga and Europa League this season
