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Coleman was incensed by Martin’s delay in giving him an answer over a proposed loan move to the Stadium of Light after the two clubs agreed terms.
The former Wales boss is still confident of strengthening his squad in the next 24 hours but will now look elsewhere after losing patience with Martin.
“We were disappointed in the end with the outcome of that,” said Coleman.
“We were told that someone wanted 48 hours, which turned into another 48 hours and that was it - we just came away from it because you can’t be begging players to come.
“It’s the opposite of the type of player we are trying to attract in terms of mentality so that completely fell flat.”