The former England defender, 46, posted on X to promote an episode of his podcast featuring Rooney. Alongside a clip, he wrote: “Do not compare this animal to the likes of Kane, Shearer and them mans pls… most Complete CF in Premier League History.”
To emphasise his point, he attached a screenshot which appeared to show Rooney scoring a hat-trick in a 4-0 Champions League win against AC Milan at Old Trafford in 2010.
But the image was fake.
It included a poorly photoshopped picture of Rooney celebrating in front of David Beckham and Ronaldinho, both looking dejected.
Milan were also shown in an all-black kit, rather than their traditional red-and-black stripes.
The match in question – a round of 16 second leg – did finish 4-0, but Rooney scored twice, with Park Ji-sung and Darren Fletcher adding the other goals.
Ferdinand partnered Nemanja Vidić in central defence that night, making it notable that he did not recognise the errors.
In the podcast episode, Rooney spoke at length about Harry Kane, comparing him to former Roma forward Francesco Totti.
Rooney said: “He’s a clever lad Harry and he knows he’s never been the quickest but I think he’s lost a little bit of sharpness. He scored I don’t know how many goals last season for Bayern. He’s a goalscorer, he’s clinical but he’s clever in terms of the positions he’s picking up.
“I watched Bayern Munich in the Club World Cup and it was almost like (Francesco) Totti for Roma, where he’d drop in and there’s runners off of him.”
Rooney added: “Gradually as the ball got further forward and they might come back out and went back round the other side, he then makes his way in the box. So it’s not a sprint but he’s in there and he’s in and around there and if he gets a chance, he scores.
“For me, he’s the greatest ever England number nine.”
When asked whether Kane had become a better player than him, Rooney replied: “As a player, I’m not sure. I think I could do things which potentially he couldn’t.
“I was nastier than him as well. In terms of goalscoring, he creates goals. People say, ‘Oh, he’s scored against San Marino or this team.’ He scores every game. Does he play well all the time? No, but for me he’s above everyone.”