Tottenham Hotspur fans were subjected to antisemitic abuse from a section of the travelling West Ham United support during their 3-1 derby victory.
The Football Association will consider whether to investigate the matter, after it studies reports from the various match officials and delegates and, although the managers from both clubs were nervous about making comment, the situation brought discomfort to Tottenham.
It was only last Thursday that a group of the club's travelling fans were attacked in Rome, before the Europa League tie against Lazio and, inside the Olympic Stadium, there were antisemitic taunts from some of the Lazio support. Uefa has opened an investigation and is expected to pronounce on the subject this week.
At the derby here in London, West Ham supporters chanted "Viva Lazio", along with other more unsavoury chants. There was also hissing from the away seats, supposedly in imitation of the sound of gas.
Sam Allardyce, the West Ham manager, said he was so consumed with the game that he did not hear the stands. "I don't hear what the fans say or do when I'm concentrating as a manager on a game of football," he said. "They shouldn't be doing things like that, should they? But it's the least of my worries at the moment.
"I never heard it so I don't know. What do you want me to say? If I didn't hear it, I can't condemn it. I'll make a comment after I've listened to what they've said. I don't want to be a political animal. I'm here to talk about football, not what fans are saying or singing."
His Tottenham counterpart, André Villas-Boas, was uncomfortable when the subject was put to him and, as he attempted not to deflect attention from the victory, it seemed as though he could only have heard the "Viva Lazio" taunt, together with the chanting of the name of Paolo Di Canio, the former West Ham hero, who also played for Lazio.
"It is difficult, you can interpret it in various ways," Villas-Boas said. "I prefer not to mar the performance with the situation like this. We know the animosity there is between Tottenham and West Ham. As long as it doesn't reach stupidity, it is a great, great rivalry between two London clubs. Although I understand the question, it would be extremely unfair of me to mar the performance of the players. I understand the whole situation is unavoidable, although we can't decipher the complete meaning of what they were singing."