The Millers training ground reopened on Monday after being closed following an outbreak of Covid-19 among staff and players, with the club having seen their last scheduled previous fixtures all postponed.
A number if players who now been in quarantine in line with government guidelines and have tested negative have now returned to training.
Other players and staff are still self-isolating, including Warne, who will miss the games with Watford and Bristol City.
Goalkeeping coach Andy Warrington took training today (Monday) and assistant manager Richie Barker should be back tomorrow to organise sessions and take on dug-out duties for Tuesday’s game.
Warne said: “We have got hit hard really hard, it goes without saying. It has hit the staff and players really bad this time; more than half of them and we have taken a big hit.
“Training today (Monday) was the first day on the grass since the Sheffield Wednesday game and the first day back in.
“I had my goalie coach Andy Warrington take the training session with Shaun MacDonald and Richard Wood and I should have Richie Barker on the side of the pitch tomorrow with him being okay.
“A few players will be in the starting 11 who have not been great. They have got through training today and we will just have to reach out for them tonight to make sure they have had no ill effects.
“I am not going to risk anyone’s health for a game of football. But if there’s a chance they can play and they want to play and there’s no physical risk, then great.
“We have had training today and a few of the lads who we thought would be able to start the game have struggled to say the least. If anyone has been through this disease and come out of the other side, they will realise how exhausting and debilitating it is.
“Even after ten days of self-isolation, to come back and suddenly be an elite athlete again is a massive, massive step.
“There will be players on the pitch who have quite obviously been through the virus, but are negative now. They won’t have problems as such, but a lack of training in their legs and are not 100 per cent.
“But we will pick a team to be competitive and there is no massive expectation on us. We have played a team who have won seven out of eight games. If we play against Watford with the best team we have ever had, it would still be a difficult game."
Admitting that in an ideal world, he would wish the game not to be played, but pragmatic about the situation, Warne - whose side are in the bottom three, but have several games in hand on their rivals, said: “Selfishly, I wouldn’t. But I completely understand the tightness of the schedule.
"I have gone on the record a few weeks ago saying the season should be extended by a couple of weeks, but I appreciate all the ramifications throughout the league as we have big games to fit in and have got to ask teams to re-adjust their schedule to allow us to play these games.
“You can also understand from a competitive point of view and if it was the other way around and a team was asking me a favour to help them out and I was fighting at the bottom half of the table, would I really want to help them out?. Selfishly, I’d want to look after my team first.
“It is not an ideal situation."