"Bradley wanted to go and we cannot keep hold of a player who doesn't want to be here," Garcia told reporters after Thursday's 1-0 Italian Cup last-16 home win over Sampdoria.
"He has done very well for me over the last few months and I understand he wanted more playing time but when there is a midfield like ours it's hard to find spaces."
Bradley was left out against Sampdoria as media reports surfaced that he was set to move to Toronto.
The 26-year-old played 41 times for Roma after signing from Chievo Verona in 2012, scoring two goals.
Media reports have also said Tottenham Hotspur and England striker Jermain Defoe is poised to join Toronto.