"For me there is no doubt Rafa Benitez is a better coach than Grant and the statistics are there," said Mascherano.
"They have a nine-point advantage over us but I don't see that reflected in the way both sides play. Chelsea are second in the Premier League but they don't have the strength and power of previous years.
"They have dropped points where previously they would not have done. That is a sign of weakness that we have to exploit.
"Historically we have got the better of them and that will be in their heads."
Mascherano claims that the players are being kept in the dark over the off - field controversy regarding the owners, and said: "We don't know much about the internal conflicts."