It’s up front where United have the least amount of options but they do have players in attack in excellent form.
Morgan Gibbs-White and Iliman Ndiaye have been superb of late and the onus will be on them to get the goals United need to take the advantage going into Tuesday’s second leg at the City Ground on Tuesday.
Heckingbottom said earlier in the week: “Bill’s (Sharp) another few days closer. We’d like him to be (able to play), if he's available to play some part in the tie.
"If he’s not ready, he’s not ready. He is doing all he can and the staff are doing all they can to make sure there is that opportunity.”
“Morgan (Gibbs-White) has been back on the grass today (Thursday),” added the Blades boss.
"Conor (Hourihane) and Morgan didn’t train last week.
"We’re fine. George (Baldock) has had more training minutes in him, he’s looking good.
"Touch wood, everything at the minute is as good as it can be.”
Baldock returned to the substitutes bench against the Cottagers having limped off against Bristol City on Easter Monday with a hamstring injury.