The 22-year-old has enjoyed his best 12 months yet in a United shirt and is on a 30-man shortlist for the prize, which will be announced on 31 December.
Fans, top journalists and an expert panel consisting of former players and managers have until 30 December to vote for the winner. Defender Thiago Silva is the reigning holder of the trophy, while Manchester City's Maicon (then with Internazionale) won the award in 2010.
One of Rafael's defensive partners at United, Jonny Evans, recently admitted the young Brazilian "sets the tone for the rest of the players" at the club with his energy and enthusiasm.
"He’s a credit to himself," Evans said. "He’s going to be one of the best right-backs in the world, no doubt about that.”
You can cast your vote for Rafael at the Samba Foot website. Paris Saint-Germain's Thiago Silva is again nominated, as are the likes of Daniel Alves (Barcelona), Diego (Wolfsburg), Hulk (Zenit St Petersburg) and Felipe Melo (Galatasaray). Other English-based nominees include David Luiz (Chlesea), Ramires (Chelsea) and Sandro (Tottenham).