Anthony Martial was the world's most expensive teenager when Manchester United signed him from Monaco in 2015, and now he's just cost them 10 million more.

Louis van Gaal signed Martial in 2015 from Monaco for an initial fee of right around 43 million, which could surpass 60 million with add-ons.

One of those add-ons was 10 million if Martial scored 25 goals in a Red Devils shirt. And that's what he did on Sunday.Martial scored a goal and added an assist in a 2-0 win against Burnley in the 2-0 win, but that goal is what will cost United a cool 10 million because it was his 25th since joining the club.

Martial scored his 24th goal for United back in February, but it took over a month for him to get to 25. His next goals could be worth a lot more than the 10 million this one cost though. Manchester United have a clause in their contract with adidas that means they'll lose more than 20m in sponsorship income if they fail to qualify for next year's Champions League, so any Martial goals that push them into the top four will be plenty worth it.

With Zlatan Ibrahimovic out for the rest of the season due to injury, it means Martial might have to be the one to fire them into the top four. Even if it keeps meaning cutting more checks to Monaco.

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