The 21-year-old has scored 12 goals for the Posh so far this term, with the team putting a 2 million valuation on him.
"We have the data which says Ricky is best presser in League One." MacAnthony told the Hard Truth podcast.
"Of course he should have 20 goals by now and the fans have a right to moan, but some of it has been over the top. If Posh fans don't want him I will have clubs offering millions for him in the summer. I already have.
"I can point to 10 games when Ricky has made a big impact on games we have won. Northampton at home is one. Without his pressing, and with Joel Randall behind him we would not have scored the goals we did and Northampton might have even nicked that game.
"Look at the points per game we accumulated when Ricky started playing as a center forward compared to the points per game before he was a regular. We had top two form and Ricky played big parts in us winning at Derby and Blackpool and in other important games. We won those games because of the way we play."