Liverpool simply don't lose Merseyside derbies at Anfield.

That was the consensus until Everton rocked up and grabbed all three points through Richarlison and Gylfi Sigurdsson on Saturday evening, anyway.

The Brazilian latched onto a superb through ball from James Rodriguez to score inside three minutes. 

Sigurdsson then doubled the Toffees' lead late on from the spot after Trent Alexander-Arnold was judged to have fouled Dominic Calvert-Lewin. 

It all means Liverpool have now lost four home games in a row in the league for the first time since December 1923. 

The champions can't have expected that by this stage of the campaign, they'd actually be level on points with Everton. 

The Blues do deserve enormous credit for another benchmark of their progress under Carlo Ancelotti, but their rare triumph across Stanley Park wasn't without controversy. 

So let's take a look at the penalty incident. Alexander-Arnold was helpless on the floor and couldn't have meant to trip Calvert-Lewin. At the same time, it was a clear goalscoring opportunity with Alisson having parried the ball loose. 

Momentarily, it looked as if referee Chris Kavanagh was going to overturn it when he made his way over to the VAR monitor. As we've seen this season, nine times out of 10, that means the decision is being changed. 

It took the official just one replay, however, and he'd seen enough. He duly pointed to the spot again. 

Many fans would like VAR replays to be conducted as quickly as possible, but Jurgen Klopp was not happy afterwards. 

In his post-match interview, the Liverpool boss questioned why Kavanagh had taken just seconds to consider the decision. 

"The ref thought it's a penalty," Klopp said in his press conference. "So I wanted to talk to him now after the first few interviews I had, but they left already. I just want to ask, so what did he see. 

"Because refs, the way VAR calls you over, in a situation like that, and I think he is in doubt over the decision. But he needed only a second!

"So he went there, watched it from three, four yards and 'yeah, pen', and went and turned and pen. So he saw something, all other people didn't see."