The Brazil international moved to England from Internacional in 2012, but has revealed current Chelsea boss Jose Mourinho wanted him to move to Madrid.
Oscar said the Portuguese came to watch him in an international friendly against Denmark, but the 22-year-old was put off due to the level of competition at the Bernabeu.
"A month before signing for Chelsea I was very close to doing so with Real Madrid as Mourinho said he wanted me," he told Globoesporte.
"They came to watch me in the game against Denmark.
"Before the games there were talks with Madrid, but they had the playmaker position well covered. After the games, I signed for Chelsea."
Oscar has scored four times in all competitions this season, helping Chelsea to fourth in the Premier League and top spot in UEFA Champions League Group E.
"He (Mourinho) talked to me as soon as I came to Chelsea," Oscar continued.
"He gives me confidence and I'm trying to return all such support on the pitch."
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