Matt O'Riley says a chat with Celtic boss Ange Postecoglou convinced him to ignore rival interest and sign for the Scottish Premiership club from MK Dons.
The midfielder, 21, has committed to Celtic on a four-and-a-half-year deal for a fee believed to be £1.5m.
The 21-year-old came through the ranks at Fulham before moving to League One MK Dons in January 2020, scoring nine times - seven this term - in 52 games.
"It feels amazing, it's a massive club," said O'Riley.
"There were other options, ones I thought were the only ones, until Celtic came out of the blue.
"I had a phone call with Ange (Postecoglou) and he came across really well. As soon as I got off the phone I was ready to come."
Capped by England at Under-18 level, O'Riley is Celtic's fifth January signing, following Japanese trio Daizen Maeda, Yosuke Ideguchi, Reo Hatate and Irish teenager Johnny Kenny.
"We're delighted to get Matt," said Celtic Postecoglou. "He's a talented young player and will add to what we've already started."
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