Alves has scored four goals in the Premier League this season
Afonso Alves will miss Middlesbrough's two remaining games this season after breaking his foot in Monday night's 3-1 defeat by Newcastle.
The Brazilian striker was tripped by Nicky Butt after 31 minutes and had to be carried off moments later.
Butt received a yellow card but Boro manager Gareth Southgate pointed to the incident as the game's turning point.
"It was a deliberate foul, it looks like he's broken his foot, it was a big moment in the game," said Southgate.
Alves, who joined Boro from Dutch Eredivisie side Heerenveen for £10m in January 2008, has struggled for form this season but is the club's top scorer with four goals in the Premier League and three in the FA Cup.
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