Manchester United's first team squad have been cleared to return to training after further testing revealed the group is free of coronavirus.
The club announced on Thursday that the planned friendly with Preston North End had been cancelled after "small number" of players and staff returned positive results after taking lateral flow tests.
However, follow up PCR tests -- usually more accurate -- have all returned negative results.
A statement issued by United on Friday read: "After further testing yesterday and today we can confirm that there are no positive cases within the first team group.
"Following consultation with the Premier League they are satisfied that all COVID protocols have been followed correctly and the squad can return to training immediately."
The decision to cancel the game with Preston leaves Ole Gunnar Solskjaer with just one more warm-up fixture before the start of the Premier League campaign on Aug 14.
A United statement issued on Thursday read: "Maintaining Covid security is a priority for us. Following routine testing of the first team training group today, we have identified a small number of suspected positive cases. This has led to those people isolating, pending further tests.
"As a precautionary measure based on COVID protocols, we have taken the difficult decision that we will not now be able to play the friendly match against Preston North End this Saturday.
"We regret the disruption to Preston and disappointment caused to fans. Any Manchester United fans who have purchased tickets for the game will be automatically refunded.
"At this stage, we do not expect further disruption around our forthcoming matches, but we will continue to follow Premier League protocols in this regard."