The Teessiders will officially unveil Dutchman Marvin Emnes and French counterpart Didier Digard on Wednesday after making a total investment of around £7.2million.
"There are a couple of other players where we are monitoring the situation with their clubs," said Southgate. "I´m pleased we have got two players in. With any other players, if it takes a bit of time, then so be it."
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