Wilder’s Northampton Town side blazed a trail through League Two last term, winning the league with 99 points - 13 clear of second-placed Oxford.
After replacing Nigel Adkins as manager at Bramall Lane, Wilder elected to release 10 players - including centre-halves Jay McEveley, Harrison McGahey and Terry Kennedy - while loan defenders David Edgar and Alex Baptiste returned to Birmingham and Middlesbrough respectively.
Wilder - currently without a recognised, senior centre-half - has, unsurprisingly, put three new defenders at the top of his summer shopping list: “Obviously defence is something we’re going to have to look at,” he admitted.
“But, in John Brayford, we’ve got the best full-back in the division when he’s firing on all cylinders. That’s what we’ve got to get him back to.
“Chris Hussey, on the other side, gives us a really good balance. He likes to get forward and cause problems but, like John, can defend too.
“And that’s important because, as much as we want to score goals, we’ve got to show that determination to keep them out at the other end too.”
Wilder’s words, however, should not be interpreted as an admission that United will not take the game to teams when the season kicks off on August 6.
“We want to be attacking but we want to play in the right areas,” the United boss added.
“There’s no point in taking stupid risks, I don’t think. The most important type of football we want to play is winning football.
“That’s the most important thing.”
United, who begin their new League One campaign on August 6 away at Bolton Wanderers and will host Crewe in the first round of the EFL Cup, returned to their Shirecliffe training base for pre-season indoor testing yesterday.
They will begin their pre-season preparations on grass on Monday and Wilder said: “There’s no easy way through pre-season, and the lads understand that.
“They’ll come back in better shape than days gone by, but there’s no getting away from it. It’s an individual sport, and I want to see players doing everything they can to get into the team on day one.
“That’s got to be the target for all the players. We want pre-season to be interesting but they’ll still have to graft and work hard.
“We’ll keep them interested and hopefully, they can put in the performances we require when the season starts.”
Meanwhile, former Blade Florent Cuvelier has joined Walsall for the third time after signing a one-year deal with the Saddlers following his Bramall Lane release.
United will travel to FC Halifax Town on July 19 (7.45pm) in a pre-season friendly.