The Blades’ confidence is sky-high after three successive wins have seen them climb to within 11 points of second-placed MK Dons with two games in hand.
But with Yorkshire rivals Doncaster Rovers and Bradford City in close pursuit – plus Chesterfield from just over the border in Derbyshire – Clough is taking nothing for granted with over a third of the season to be compressed into the final few months.
“We are still not giving up on the top two, but also we are not even assured of a top-six place yet,” said Clough.
“There’s still plenty to go at.
“Bradford have only lost a couple of games since November, they are in a very good run of form, as are Donny.
“Chesterfield and Oldham are still in there, so we are not even assured of a top six.
“Anyone down to about half way have still got designs on the play-offs.”
Rovers, Bradford and Chesterfield have all still to visit United – they are the Blades’ final three home matches of the campaign.
Plus, United have already played the top four – home and away – meaning all their games now are fixtures against sides lower than them in the table.
Clough is tipping Bristol City to be champions, but believes the second automatic promotion spot is “up for grabs”.
He said: “We looked at halfway, and a couple of teams had 54. I can’t remember the last time someone got 108 points. It’s very unlikely they can replicate that form in the second half of the season.
“Bristol City have got the most capability of doing that and I still think they will win the league.
“But I still think that second spot might be up for grabs.
“Even the small fact that we have done playing the top four helps. You might say you want to play them to take points off them, but you look at the games on paper and we haven’t got to go to those four places.
“Bradford have got to come to us, Chesterfield and Doncaster have still got to come to us. So three of the four clubs chasing have still to come to Bramall Lane.
“The top four have all got each other to play as well, so that’s a benefit to us.”
Whatever the results elsewhere, Clough knows United can only focus on their own games, starting today with the visit of struggling Coventry City.
After being in a similar league position to fifth-from-bottom Coventry 12 months ago, Clough has plenty of sympathy for his opposite number Steven Pressley.
“Steven has had a tough time in the last year,” said Clough.
“They had a great start to the season, like a few teams, but it’s difficult sustaining that over a long period.
“They will be nervy at the moment, more than anything. You are desperate for a point, just not to lose games.
“We know from our experience 12 months ago, you would do anything to get a 0-0 away from home. From there you might nick a 1-0.
“It’s always a big occasion for most teams when they come to Bramall Lane. Coventry might be one of these teams who thrive on it.
“We can try and exploit the nervousness of their position, I don’t think they will come out all guns blazing.
“It might have to be a patient day for us, don’t give them any encouragement, anything to give them confidence.
“We have all been in the situation, you go out desperate for a point or three to get away from that bottom four. It’s not a nice position to be in.”
The Blades have taken 12 points from a possible 15 in their last five League One outings, including impressive wins over top two Bristol City and Swindon Town.
With 17 games remaining, Clough’s message to his team is “more of the same please”.
“Four wins out of five, and just the blip at Gillingham,” he reflected. “Even then we are just four minutes away from getting a 0-0.
“It’s funny, the away wins give you as much confidence as anything. To win, under the circumstances, at Bristol City then a battle at Notts County, that gives us confidence.
“We played well in both games and deserved our victories.
“It’s a matter now of just keeping doing the same things, improve on the small things that we are not doing very well, and don’t make mistakes.
“It’s very simple, but when you get to this stage of the season, that’s all it is.
“Just keep things going, we don’t have to change anything.”
Clough accepts he cannot avoid tinkering with his starting XI to cope with the demands of a congested fixture list.
And he has been full of praise for Barnsley-born defender Terry Kennedy, 21, who has stood out in recent weeks.
“I don’t think we are in a position where we can keep a settled side,” said Clough.
“We can’t put the same XI out from now until the end of the season, even if they are all fit.
“People are carrying knocks. Terry Kennedy had done really well in the last couple of games, but he starts feeling his knee, and has to be managed during the week. We missed him in the first couple of months.
“But since he has come back, every time he stepped in he hasn’t let us down.
“You know what you are going to get from him, he gives you absolutely everything, and doesn’t let you down on the pitch.
“You know his commitment level will be spot-on. Against Matt Smith last week, to win as many headers as he did, against someone who is eight inches taller, that says everything about his desire and determination.
“Terry is one of those lads, that whatever level he was playing at, he would be the same.
“If he was playing Sunday morning for his pub team, he would play exactly the same as he does on a Saturday afternoon.
“He just enjoys playing, heading the ball, defending.”