Friday's Estádio do Dragão clash descended into chaos immediately after the final whistle, with players, substitutes, and staff all flooding the pitch in an elongated scuffle.

Clashes between Porto and Sporting CP, two of the biggest teams in Portugal, are always heated. However, the two teams took their rivalry to a new level on Friday when they kicked off Matchday 22 in the Primeira Liga at the Estádio do Dragão.

Given that the Dragons are the league leaders while the Lions are both the defending champions and Porto's closest rivals, this meeting was always going to be fiery. The game began with a six-point gap separating these two clubs, meaning Rúben Amorim's second-placed side could not afford a slip-up if they were to remain in the hunt for the league crown.

The visitors got off to the perfect start, with Paulinho giving them the lead after eight minutes before Nuno Santos doubled their advantage shortly after the half-an-hour mark. However, in unfamiliar fashion, the Lisbon giants threw away their huge lead, with Porto pulling level thanks to goals from Fábio Vieira and Mehdi Taremi in the 38th and 78th minute respectively.

Sebastián Coates was sent off in the 49th minute, which played a part in Sporting CP's inability to secure the win, but while that was the only dismissal within normal time, the Uruguayan center-back was not the only player to be given a red card as the match descended into chaos at full-time.

The catalyst for this near five-minute brawl was an incident involving Pepe and Joao Palhinha, with the Porto center-back apparently getting caught in the head by a high boot from the Portuguese midfielder during the home side's last-gasp attempt to win the game. The former Real Madrid defender remained on the floor but was not awarded a penalty, with the action continuing for another minute before the referee blew his whistle.

Tempers boiled over, with staff and the substitutes from both teams joining the men on pitch, leading to a heated and elongated scuffle. Initially, three extra players were shown red cards as Joao Palhinha and Bruno Tabata were sent off for the visitors while Porto's Agustin Marchesin was dismissed.

A while later, Pepe lost his cool after the match official refused to listen to his plea for a penalty and was eventually sent off himself. Even a ball boy got involved in the action, with both managers later making their way onto the pitch in order to break things up and get their players into the dressing room. Watch everything unfold in the video below.

While Porto's 16-game winning streak came to an end, Sérgio Conceição's men stretched their excellent unbeaten run to 50 matches. Additionally, they've maintained their six-point advantage and remain the favorites to lift this season's title as they are yet to lose a league tie.