Rafael savoured a fourth consecutive clean sheet and praised the improving David de Gea after Manchester United moved five points clear at the top of the table with a 2-0 triumph over Blackburn.
The Red Devils have surged past Manchester City over the past few weeks on the back of a seven-match winning run in the Premier League, and a solid defence has been an integral part of their success.
Rafael again played his part in shutting out Blackburn at Ewood Park on Monday night but the Brazilian believes the contribution of De Gea was also crucial.
The Spaniard pulled off a number of impressive stops to extend his fine run of form in the second part of the season, before late goals from Antonio Valencia and Ashley Young sealed victory.
"It was very important to keep a clean sheet because if we don't let them score, it is a lot easier for our strikers to play," Rafael told MUTV.
"But if they would have gone a goal up, it is a lot harder for our strikers to play."
Speaking about De Gea, Rafael added: "He is just top-class. He is young and keeps improving. I think he can improve even more in the future."
Rafael also paid tribute to the performance of Valencia, who broke the deadlock with a powerful strike from a tight angle that flew past Paul Robinson.
"Antonio is just superb. He plays very naturally and keeps going and going," said the full-back.
"He is getting better and better with each game. They had 11 players behind the ball so it was hard for us, but thankfully their goalkeeper didn't see Antonio's shot for the first goal and it went in to give us the lead."