"Everything has been agreed between the clubs and I'm absolutely delighted we have got a player with big potential whom I have worked with before," he said.
"I brought Frank into the reserve team at Chelsea when he was 16 and I never forget a session where we had a training game after we'd just signed (Branislav) Ivanovic.
"Frank was up against a £10milion player but his performance that day took all the coaches by surprise.
"He was absolutely incredible. It was an amazing display from such a young guy. But I remember thinking that day that he had all the tools to be a top player in the Premier League.
"Players like him don't come around often but this is the perfect place for him to come on loan. Frank knows me and he's coming to a good place. He will be a great addition to the squad."