Dean Smith has admitted there should be a "magic number" for the amount of Covid-19 cases a club needs for a Premier League fixture to be called off after his depleted Norwich side suffered a 2-0 defeat at home to Aston Villa.
The Canaries were without Lukas Rupp, Pierre Lees-Melou, Christos Tzolis and Josh Sargent due to coronavirus concerns - in addition to several other squad members being absent with injuries - and were consigned to a third straight loss after goals by Jacob Ramsey and Ollie Watkins.
Manchester United saw their scheduled fixture at Brentford on Tuesday postponed due to Covid-19 cases in their camp and Tottenham were also able to call off last weekend's match at Brighton, but the likes of Norwich, Leicester and Brighton have played recently with players unavailable due to the virus.
"Our sporting director (Stuart Webber) spoke to the Premier League on guidance when we have symptomatic players around us," Smith explained after the defeat to the club that sacked him last month.
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"We played Tottenham, they had an outbreak. We played Man United, they had an outbreak. We wanted guidance over would it be fair on Villa if we had symptomatic players around us?"
He continued: "I am not saying all our players are symptomatic and have Covid because some are injured.
"Grant (Hanley) did his shoulder on Saturday and Ozan Kabak went down, so we have injured players, but we probably need a magic number telling us how many is enough."
Smith conceded he had "no idea" if there was a specific amount of cases which saw a fixture called off, but the PA news agency understands there is no official threshold for the number of positive cases that would cause a game to be postponed.
Rival bosses at Brentford and Arsenal in Thomas Frank and Mikel Arteta made similar calls for clarity earlier this week, while the Premier League has brought in daily lateral flow testing for top-flight clubs and PCR testing will increase to twice a week.
The Canaries boss had to delay naming his starting XI for the clash with Villa and another injury during the loss saw Sam Byram make his first appearance in close to two years following repeated hamstring problems, with a trip to West Ham on Saturday up next.
"What we don't want to be doing is taking risks going into games where there is an opportunity for it to be passed around during a game," Smith added.
"I don't know [about West Ham]. I will find out over the next 48 hours from the medical staff about our cases. I have seen new Premier League protocols where we are tested every day. The heat is on, not just across football but across the country.
"I would normally name the team the day before and could have eight players [affected] who would be in the first team. Then the fact Ozan goes down and Sam Byram makes his first appearance in two years, we are down to the bare bones. I don't want to make that excuse but there are reasons why we were off it."
Smith's successor Steven Gerrard was delighted to watch his new Villa team secure a fourth win from six matches since he took over in November.
"The plan was to try and finish the game early and try to find the second goal earlier," Gerrard insisted.
"At 1-0 you always run the risk [of conceding] so it was nice to see Ollie finish it off. The academy deserves a lot of credit. We've some top coaches and we need to keep developing it as we want as many local homegrown players that we can have.
"It has been a challenging week, we lost one to injury, a couple to Covid and some members of staff as well.
"It's been a positive start for me and we've started how we wanted to do and had some really tough games against (Manchester) City and Liverpool."
"The week has been challenging, losing staff and players and having to cancel the [training] session on Sunday, but I thought first half we were outstanding."
What's next?
West Ham will host Norwich in the Premier League on Saturday; kick-off 3pm. Aston Villa host Burnley on Saturday also at 3pm.