But just who is the 15-year-old talent?
HITC Sport answers those all important questions...
What sort of player is he?
Allow Spencer's mother, Heidi, to explain: "Morten is very good with both feet so they tend to put him on the left wing but he can also play in a central midfield role," she told the Teesside Gazette last summer.
"He’s very creative, he’s a good passer of the ball, good at dribbling and he’s got a helluva shot. He’s very strong, fit and fast and has grown quite a lot lately so he’s now around 5ft 10ins. He scores a few goals as well."
Morten's an unusual name...
Well not in Norway, where his mother is from. However, it is with England, at under-15 level, that Spencer has gained international recognition. "We actually sent some video footage to the Norwegian FA but we haven’t heard anything back," explained Heidi to the Teesside Gazette.
How long was he at Sunderland for?
Six years, according to his mother, who told the Teesside Gazette last summer that Spencer "has been offered a scholarship with Sunderland and that starts when he’s completed his GCSEs." Thanks to Leeds, that won't be happening now.
Wasn't he supposed to join Middlesbrough?
Yes. As recently as last month, Heidi told TV2 in her native Norway: "(Middlesbrough is) so close that we can stay here we live now. In the long term, we believe this is the best solution for Morten's development."
She also explained why the family chose to reject the advances of Manchester City, adding: "Manchester City is one of the clubs that has shown interest. In the beginning, Morten would probably also get there, but that would mean that he had to move away from home to live and play there. Eventually, we have felt that City is such a large club with quite a few talents that are eventually sent out on loans. Therefore, we have looked at other alternatives."
How much have Leeds paid?
That remains unclear. However, The Sun reported that Manchester City were likely to have to pay around £200,000 for Spencer, with Sunderland "also making sure they are entitled to a slice of any future profits".
Will the former Sunderland talent prove a good addition for Leeds?
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