Louis van Gaal rejected accusations he has a poor relationship with Manchester United assistant manager Ryan Giggs.
The Dutchman reacted with elation to United's late winner at Newcastle on Wednesday but his second in command, Giggs, was much more muted, even when Van Gaal touched him on the cheek a couple of times, prompting speculation.
But Van Gaal said he was annoyed with stories that the duo, who were paired in a new-look management team last summer, have had a falling out.
"We have a very bad relationship," he joked in a news conference. "A very bad relationship.
"I'm very irritated by this question. We have a very good relationship, everyone can see that we work very hard together, and that goes for all the staff and players. I think it's a way of suggesting things, so I'm very irritated. I'll take this up with the media, I'm not pleased."
Van Gaal also hit out at stories that United were planning to spend in the winter transfer window when their only signing, goalkeeper Victor Valdes, joined on a free transfer.
"You know how many players I should buy in January," he said. "I said in all my press conferences we don't buy so you have to believe me."
And Van Gaal insisted his comments that United strikers Robin van Persie and Radamel Falcao, who have only scored 10 and four goals so far this season, are not 20-goal-a-season was merely a statement of fact, not a criticism.
"I cannot deny that Van Persie or Falcao did not score 20 goals but not any striker has scored 20 [Premier League] goals. I cannot deny they did not score 20 goals. I am always a facts man."
United face Arsenal on Monday in an FA Cup quarterfinal that Van Gaal believes is like a final.
"United and Arsenal are placed third and fourth in the league, so it's almost like a final, I think," he said. "It's very important, every match that you play has an influence on the next. We are in a rat race in the Premier League and the club that wins the FA Cup match on Monday will have good momentum for the league games."
Van Gaal explained the absence of left-back Luke Shaw from the match at St James' Park.
"Luke Shaw had a tight hamstring," he added on MUTV. "We don't take risks with any players."