Jokanović was sacked last week with the Blades 16th in the Championship after 19 league games, and 18 points off the automatic promotion places.
United were amongst the bookmakers’ favourites to go up this season, having only been relegated from the Premier League earlier this year, but struggled to consistently piece together results under the former Fulham and Watford promotion winner.
Sharp scored United’s second goal in Sunday’s 2-0 win over Bristol City, Paul Heckingbottom’s first game in charge since being named as Jokanović’s permanent successor, and the United skipper said: “We've got to keep diving each other on.
“Every single day counts. I spoke to the previous manager about our standards in training not being as good as they should have been, and it leads into a game on a weekend or in midweek.
“We've got to be at each other every single day so it gets easier on a Saturday afternoon.
“The manager two managers ago [Chris Wilder] always used to drive on about standards in training. If someone isn't doing it, then make sure they’re pulling their weight.
“Hopefully we can get there quicker than it's taken this season to get our standards back to where they should be and where we want to be.
“We're teammates, and that's what it's all about. If one of the lads isn't doing too well, you've got to pick him up and go again.”