"I'm really happy to get Gary Neville's old number," the Brazilian said. "He's a club legend so I'm happy to wear his shirt."
But will it change the way Rafael plays when he steps onto a football pitch?
"Not at all," he said. "I wouldn't say there's more pressure on me now. Whenever you play for Manchester United's there's pressure."
Perhaps shirt numbers just give us something else to talk about in this era when fans crave constant debate and analysis.
Surely, though, what really matters is how a player embodies the spirit of the club crest emblazoned on the front of his shirt... not whatever number he happens to be wearing on his back.