The boss has held talks with Mascherano and his agent about a new contract for the midfielder and has revealed that the discussions were very positive.
"We were talking with him and his agent a month ago about our idea and his idea," said Benitez.
"He's doing really well and has come back to his best. We were really pleased to talk to him to make progress. We have plenty of time but we are happy with him and he is happier now, too.
"He has two more years on his contract, we were talking before and we will sit down sooner rather than later and talk about the future.
"The last conversations that we had were very positive."