Steve Bruce hailed the swift response to Newcastle's coronavirus outbreak as he revealed the situation could have been significantly worse had the club's training ground stayed open.
A number of players and staff contracted the disease earlier this month, leading to their training headquarters being closed for more than a week while the Premier League game at Aston Villa on December 4 was postponed.
Bruce is optimistic the Magpies have "overcome" the worst of the crisis, with Federico Fernandez's latest negative test giving the Argentinian defender the all-clear to return to the ranks for the trip to Leeds on Wednesday night.
Isaac Hayden was one of three players who recovered from Covid-19 to feature in the weekend win over West Brom but two others are expected to be absent for another fortnight as they continue to deal with the effects of the virus.
The identities of the pair were guarded by Bruce, who admitted he was taken aback by how quickly the disease swept through the club.
"The vast majority of the players are young, fit and healthy, and it washes over them," the Newcastle head coach said. "But we've got two players in particular who are not well at all.
"I think it would be wrong for me to go into details but they're not going to be ready for at least a couple of weeks.
"Isaac was in bed for a week and arguably he's our fittest player. It has no boundaries, I think (being fit) helps you recover better but it shocked me. The way it skittled through everybody was quite scary.
"(Players and staff have) had three negative tests in the past six days so it does look as if we've overcome it.
"The decision to shut us down...was crucial otherwise God knows what it would have done, it would have ripped through everybody, the way it was going. It was ridiculous, I have to tell you."
Scottish winger Ryan Fraser is also in contention to return to face Leeds, having been sidelined since November 1 with a hamstring injury, while Bruce anticipates making "two or three" changes to the side that beat the Baggies.
Newcastle's trip to Elland Road will be their first in the Premier League in 17 years and Bruce is relishing the opportunity to go up against Marcelo Bielsa, who has rejuvenated Leeds since his arrival in the summer of 2018.
The Argentinian's unorthodox methods have turned Leeds from a mid-table Championship side to one making waves in the top flight and Bruce, who hopes his side can claim a third win in a row, is a fan.
"He's unique, different, eccentric but what you can't deny is how very, very good he is," Bruce said of his opposite number.
"When I see Leeds be transformed from the type of team he had into what they've got, it's unbelievable what he's done. He's turned players who were doing just OK in the Championship into really good Premier League players now.
"I've never seen anybody have an impact on the same group of players that he had at Leeds. They went from being average in the Championship to the top of the Championship.
"Physically they're number one in the Premier League. To come from the Championship and be that stat is remarkable in itself. We've all got the hugest admiration for him because he's been there, done it and worn the t-shirt."
