Wolverhampton Wanderers have now won just one of their last seven matches, and conceded seven times in their last two games.
Wolves have conceded seven goals in their last two matches – against Leeds United and Sheffield Wednesday.
The sheer volume of goals the side have conceeded has cost them any chance of getting points from their last two fixtures, and Jackett admits that a big improvement is required.
"We deserved nothing out of Leeds and Sheffield Wednesday because of our defending - our defending as a unit has been poor," Jackett told the BBC.
"Obviously it's a concern - conceding seven goals in two games gives you no chance of earning any points.
"We need to win more headers at the back and attack it. You can see when a goal goes in there's a lack of confidence. It takes us a little while to get going again."
After losing to Wednesday and Leeds, Wolves have now won just one of their last seven matches, and have slipped down to 17th place in the Championship.
Although the Wolves attack is nowhere near as potent as it was last season, it is defensively where the current problems lie. Wolves started the season leaking goals, but they appeared to have solved the issue when they recruited Mike Williamson from Newcastle United. However, the Magpies terminated that loan move early, and since the experienced centre-back has returned to St. James’ Park, Wolves have struggled at the back.
The Midlands side have now conceded 32 times in 22 matches this season, and their chances of making it into the play offs - they are currently nine points from 6th spot - appear very slim.