Barnsley manager Lee Johnson has admitted that he was "very disappointed" to see Mason Holgate join Everton.
The 18-year-old joined the Blues last week for a fee believed to be in the region of £1.5m, but Johnson feels that the teenager has made the move to the Premier League too soon in his fledgling career.
Johnson told reporters: "I'm very disappointed Mason has gone at this stage of his career because I believe staying with us for another year would have been the best thing for his development.
"But, at the end of the day, we must have players here who want to play for Barnsley. That is the most important thing.
"We offered Mason a good contract but he turned it down. That was a shame. But now we move on and we wish Mason well for the future."
Roberto Martinez's men picked up their first victory of the season with a 3-0 win against Southampton on Saturday.
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