Saturday’s 1-0 defeat to Reading left the Millers stranded at the foot of the table, with just six points from a possible 42.
Their only win was against Brentford on August 20, and the terrible run of results cost Alan Stubbs his job last week.
It means the Millers are eight points adrift of safety, with Derby County on 14 points, but Jackett, who took charge against Reading 24 hours after succeeding Stubbs, believes there are enough points available from the remaining 32 games to not panic.
“There is a lot of time to go, the players can’t get too disappointed by looking at the table, they can’t lose their enthusiasm, that is important,” he said.
“We do need that level of enthusiasm throughout the season and some experience of the division and an ability to reduce the goals against because that has been the biggest problem so far.”
Against Reading, Jackett opted for the experience of players like Richard Wood and Greg Halford to stem the flow of goals.
It nearly brought a clean sheet, with Paul McShane’s late winner a cruel blow for the hard-working hosts.
Former Wolves chief Jackett may have only been in the post a short while, but he has been in the game long enough to recognise the problem. While United have plenty of attacking options, it is concerns at the other end that have plagued them.
Rotherham, who travel to Ipswich on Saturday, have conceded 33 goals in 14 games, the worst record in the Football League.
Jackett said: “We need to make sure we are organised off the ball and hard to play against. There have been a high number of goals this season and that has been the major problem.
“There are a few forwards around and a few wide players and we look quite creative.
“We have players in those positions that look like they can do quite well. But just collectively as a team it’s reducing the goals; staying in games and making sure we are there or thereabouts with the points is the main thing.
Rotherham last night signed free agent Peter Odemwingie on a deal until January, subject to FA and EFL ratification.
The Nigerian international becomes Jackett’s first signing.