Purches was stretchered off in the opening minutes of a game that was decided by Gary Jones' injury-time penalty.
Bradbury had no problem with the challenge between Purches and Dale midfielder Jason Kennedy that led to the injury but was left to rue the dire consequences.
"Stephen Purches has a suspected double leg break and we're awaiting confirmation of that," said Bradbury after the League One clash at Spotland on Saturday.
"It came from a firm but fair challenge - there was nothing we felt aggrieved about in the tackle. It was just a fair challenge that has finished in an unfortunate way for Purchy.
"It probably affected the lads for a few minutes, but once they got it out of their mind we gave it a good go. We had some half chances and I felt a point would have been fair.
"Rochdale made the game very difficult for us. They are fighting for their lives right now and showed great character. They stopped us playing in key areas, but I felt we deserved a point."
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