Blackman, 22, joined Rovers from Macclesfield in 2009, but only made three appearances last season as the club were relegated from the Barclays Premier League.
The Blades lost the npower League One play-off final on penalties and Wilson admitted goals are vital if his side are to cross the finish line next season.
"We've made an enquiry but that's all it is at the moment," he told BBC Radio Sheffield.
"I can't really comment further, but it's correct to say we've an interest in him. Goals will get you where you want to be."