"We have been really good in defence for three of four years, but I think we need to improve a little bit if we want to be at the top of the table," said Benitez.
"We have analysed a lot of things this year. For example, we have conceded a lot of goals from set-pieces. We need to understand why because the season before we conceded six, now it's 16, yet we're doing more or less the same things.
"We talk about how to do things properly and yet we continue doing the same things sometimes. We can improve some things.
"We also need to keep the team scoring in open play while at the same time improving a little bit in defence."