Ba has already scored twice in two appearances since his move from Newcastle and despite two defeats in the last three matches, Benitez believes he has improved the team.
He said: "I have been here for seven weeks. We're scoring more goals, conceding less and playing nice football.
"We played really well against Swansea, much better.
"There were clear chances and good football but we conceded two goals and lost.
"The players are happy, the staff are doing a great job and doing their best every day.
"Things are going in the right direction. Top sides expect to win every game and you can't."