Bundesliga referee Patrick Ittrich admitted his disappointment at the length of a VAR review during Borussia Dortmund's 4-2 win over Union Berlin.

VAR intervened three times during Dortmund winReview of disallowed Kral goal lasted several minutesThe referee spoke about the issue afterwardsWHAT HAPPENED? VAR officials took four minutes to determine whether or not Union Berlin midfielder Alex Kral was onside when he headed the ball into the net during the weekend's Bundesliga clash with Dortmund.

The decision eventually came that he was positioned beyond defender Mats Hummels.

WHAT THEY SAID: "The offside decisions are mostly factual, it just took a little long today because something wasn't right with the calibrated lines.

And we simply have to ensure safety over speed so that nothing slips through our fingers and then we just have to wait so long," Ittrich told reporters in the mixed zone.

"This is disturbing.

I can understand the fans' displeasure.

In the end, the right decision is important.

But I'm very annoyed myself.

I should have recognised it myself straight away.

"Article continues belowTHE BIGGER PICTURE: Kral's header in the 18th minute would have put Union Berlin into a 2-1 lead.

As it was, they did go ahead soon after through Leonardo Bonucci, before Dortmund scored three unanswered goals.

VAR also intervened twice more in the first half alone, ruling out a Dortmund goal for offside and awarding the penalty that Bonucci converted.

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