Middlesbrough boss Aitor Karanka has revealed that the return to fitness of Ben Gibson is vital for his team at the start of the campaign.
The England Under-21 international missed the first three matches of the season after being ruled out with a hamstring injury, but he made his comeback against Derby County in his side's 1-1 draw at the iPro Stadium.
Karanka told Sports Mole: "It's important because we don't have another player that can play in his position. The first game Dael [Fry] played and in the second it was Tomas [Kalas].
"Gibbo is the only natural player at left centre-back, so it's very important for us to have him available.
"He got injured three weeks ago and Tuesday was his first match back so I have to speak with him to see if he is ready again to play on Saturday."
Middlesbrough face Bristol City at the Riverside Stadium on Saturday.
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