AC Milan vice-president Adriano Galliani admits they didn't want to lose Bryan Cristante.
The talented midfielder has signed permanently with Benfica.
Galliani said: "The move came from the insistence of the same guy. He was impatient.
"I tried to get a loan, but he said no. So we opted for the sale, reinvesting the figure for another very talented young Italian like Bonaventura."
Bonaventura joined Milan for €7 million.
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