Feyenoord assistant John de Wolf asks fans to behave themselves after Ajax game is suspended

Feyenoord assistant manager John de Wolf told his own fans to "use your brain goddamnit" after their KNVB Cup semi-final clash against Ajax was suspended on two separate occasions.

Less than a minute into Wednesday night's game at De Kuip and play was suspended due to smoke caused by supporters.

After the flares eventually burned out, Ajax and Feyenoord returned and play continued until midway through the first half, when midfielder Davy Klaassen was hit on the back of the head by an object – believed to be a lighter.

Klaassen, meanwhile, was left with a serious wound on his head after the shocking incident and as a result, the referee hauled the players from the action again.

Moments later and Feyenoord assistant John de Wolf, with microphone in hand, confronted supporters inside the 51,000 capacity stadium with a message of his own.

"Fans, at that side, use your brain goddamnit," he said. "Make sure nothing is being thrown on the pitch again."

In terms of the scoreline, Ajax secured a 2-1 win thanks to goals from Dusan Tadic and Davy Klaassen but ultimately, the headlines belonged to John de Wolf and his inspired speech during the break.

One fan said: "Feyenoord assistant and club legend John de Wolf has just come out into the middle of the pitch with a microphone and implored the Feyenoord fans to behave themselves. Quite extraordinary."

A second wrote: "Why is he telling them off like schoolchildren, just call the game off."

A third added: "How about empty that side of the stadium rather then warning them. Just throw them out."

Taking to Twitter during the game, former Netherlands international Ronald De Boer also commented on the game, saying: "When we see this battle between two teams in other competitions, we say that we miss this here in the Netherlands.

"And now we're going to say it's the fault of the players that this game got out of hand. They probably asked for it...ridiculous of course."