Chelsea boss Frank Lampard has warned that the current use of VAR could be "dangerous" for the Premier League.
Guidance from the Premier League at the start of the season said that it would only be used for "clear and obvious" errors by on-field referees.
But when Watford were awarded a penalty via VAR after Gerard Deulofeu was tripped by Jorginho, Lampard said he was "so, so surprised".
"We're not in a great place with it," he said after Chelsea's 2-1 win.
"Any [decision] that takes that long means they aren't sure, so why aren't we using screens on side of pitch?
"I know [using screens] is a bit contentious, I know it could mean every fan might call for it and there might pressure on the referees.
"But if we are saying they are grey areas and we are overturning decisions because one referee somewhere else thinks it was more of a penalty than the referee on the pitch, then I think we are in a really dangerous place.
"You're going to be tossing a coin every week."
Watford may feel they deserved a decision in their favour after being denied a penalty, which was reviewed by VAR, in a 1-1 draw with Tottenham last month.
Last weekend, VAR awarded a penalty in the Premier League for the first time, when Everton's Michael Keane was adjudged to have fouled Brighton's Aaron Connolly in a 3-2 win for the Seagulls.
It was a decision that was widely criticised.
After VAR overruled referee Anthony Taylor at Vicarage Road on Saturday, Lampard felt there had been a change in policy despite receiving guidance at a meeting earlier this week.
"I have to be careful but last week we saw a clear change in VAR with penalties getting overturned," Lampard said.
"I was at a managers' meeting in the week and we spoke a lot about it and the absolute consensus from managers, from referees and from the Premier League was that decisions were not going to get overturned unless they were absolutely clear and obvious or VAR saw something that the referee on the pitch didn't see.
"[In Jorginho's case] it didn't, it nowhere near shows that. The longer it took the more worried I got and I'm so, so surprised after the meeting on Thursday to then have that decision today."