Liverpool extended their lead at the top of the Premier League table on Wednesday night, but you would not have known it. For many connected with the Reds, a 2-2 draw with fierce rivals Everton in the Merseyside Derby felt like a defeat.

Liverpool were 2-1 up in injury-time. With seven minutes on the injury-time clock - with a minimum of five added on - a ball into the Reds box was slammed into the roof of the net by James Tarkowski.

Chaos ensued both on and off the pitch. The chaos off the pitch actually spilled over onto the field of play. And while the final whistle sounded soon after the equalising goal, the interest was not.

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Abdoulaye Doucoure celebrated in front of the Liverpool fans, Curtis Jones was less than impressed and squared up to the Everton man, grabbing him and a melee ensued.

The two players who started it were sent off after the final whistle and they were not the only ones, with Reds boss Arne Slot and assistant Sipke Hulshoff also seeing red after the event. It was bedlam inside Goodison Park for the final derby at the grand old stadium.

And Arsenal will have been watching on interestedly at what was going on.

Liverpool have been almost flawless throughout the season so far but a derby clash is always a sticky affair. And while Liverpool did not necessarily come unstuck, with a point away at your biggest rivals no bad thing, what happened at the end will have brightened Arsenal and their hopes of lifting the Premier League title come May.

The Reds were ruffled. Slot and his players lost their cool. A nine-point lead is almost insurmountable at this stage of the season, given how good they have been. Seven just makes people wonder.

Given Liverpool have been pristine and focused for the majority of the campaign, there is a chink in the armour. Everton have shown you can get at Liverpool and get under their skin.

The Toffees had almost twice as many shots as the Reds, while the Reds committed more than twice as many fouls as their hosts. Not out of the ordinary for an away match against your big local rivals. But it was an indication to other teams in the Premier League of how to get the better of, or at least on the same level as, Liverpool.

And Arsenal will see it as a touch of vulnerability from Slot and his players, particularly given the weekend FA Cup shock at the hands of Plymouth Argyle, that they are not infallible and there is still a Premier League title battle.

The door could be ajar for Arsenal, with Liverpool facing Aston Villa and Manchester City away after this weekend's Anfield clash with Wolves. It will be a case of whether the Gunners can step through it.