The 28-year-old was presented at the Nou Camp on Sunday after completing his move from Arsenal to the Catalan side and admitted he was not yet 100 percent fit after getting injured during Belgium's 1-0 win over Russia in the World Cup, which meant the defender played just 29 minutes of football in Brazil.
The former Arsenal captain added he hoped to "start from zero" after missing most of last season with the Gunners due to a series of injuries but joins Barca as an injured player.
A statement from Barcelona said: "Thomas Vermaelen injured his right hamstring during the World Cup in June. The player will undergo physiotherapy, and the evolution of the injury will determine when he returns to training."
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