The 28 year old fell foul of Hull City boss Brown after his tantrum before their game with Arsenal at the weekend.
Speaking of the deal Middlesbrough manager Gareth Southgate said: "We have an agreement with Wigan and with the lad (King) that he should join us over the weekend on a six-month loan deal until the end of the season."
Twenty five year old Egyptian Mido is expected to move the other way. He said: "My exit from Middlesbrough is almost certain, I am 95 percent sure of that.
"I know there are talks with Wigan, and I have to say I would be happy to play alongside Zaki."
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