Manchester United were incredibly poor against Arsenal on Wednesday evening.The Red Devils were second best throughout as they succumbed to a 2-0 defeat at the Emirates Stadium.It was arguably United's worst performance since Ole Gunnar Solskjaer became manager last December.And it came in a big match against Arsenal, which made the night even more disappointing.So, when Solskjaer smiled in his post-match interview, Robin van Persie was not happy at all.

"When I listen to Ole, he sounds like a really nice guy," Van Persie said on BT Sport, per the Mirror. "I would like to see him a bit more mean at times, just be angry.

"I see him smiling now after a game like that. This is not the moment to smile.

"They need a game-plan and a bit of fear for the coach. You know if you don't make those runs or make that pass, you will be punished and you won't play the next game."

The Norwegian boss has now responded to Van Persie's comments and he hasn't held back.

“I don’t know Robin and Robin doesn’t know me,” he said, per the Guardian. “He probably doesn’t have a right to criticise my management style and I won’t change. That’s definite.

"He took my No. 20 shirt and that’s probably all he’s going to take from me because I’m not in medieval times.”

Wow. It seems Van Persie really hit a nerve there.

The Dutchman has a point, mind. Solskjaer should have been angry after his side's performance on Tuesday.

But he came across as someone who wasn't really bothered by the defeat.

Regardless, fair play to him for standing up for himself and hitting back at Van Persie.

If Solskjaer thinks he was right to smile then that's fine. He is the boss at United and he doesn't have to listen to what anyone else thinks.

We look forward to seeing how Van Persie reacts to Solskjaer's words. This may not be the last you've heard of this story.