52,000 supporters turned out to watch Liverpool take on Atletico Madrid in the second leg of their first knockout stage tie at Anfield on March 11.
Despite the fact that Spain was one of the worst affected countries in the early stages of the Covid-19 outbreak, 3,000 Spanish fans were allowed to fly to England to watch their team secure a stunning 3-2 victory on Merseyside.
The government imposed new rules regarding social distancing and self-isolation 10 days later, with all sporting events across the United Kingdom called off as a result.
Steve Rotheram has expressed his belief that preventative measures should have been brought in far earlier, while suggesting Liverpool's clash with Atletico never should have been allowed to go ahead.
"If people have contracted coronavirus as a direct result of a sporting event that we believe shouldn't have taken place, well that is scandalous," Liverpool's mayor told BBC Sport. "That's put not just those people in danger, but those frontline staff in the NHS and others in their own families that may have contracted it."
There have been 10,027 confirmed cases of coronavirus in the north-west of England to date, with 246 deaths recorded in Liverpool's NHS hospitals. Spain, meanwhile, is now second to only the United States in terms of confirmed infections, and 7,684 people have died in Madrid.
"We've seen an increase in the infection curve, and that's resulted in 1,200 people [in Liverpool] contracting Covid-19," Rotheram added. "That needs to be investigated to find out whether some of those infections are due directly to the Atletico fans. There were coronavirus hot cities, and Madrid was one of those.
"They weren't allowed to congregate in their own country, but 3,000 of those fans came over to ours, and potentially may well have spread coronavirus. So it does need looking at, and it does need the government to take some responsibility for not locking down sooner."