Boro's manager Tony Mowbray said he was unhappy with the poor defending, which led to his side's 3-3 draw with Bournemouth.
"We can't keep conceding goals," he said. "You can't give away three goals at home and expect to win. That's eight in three games now and that is far too many.
"We actually did very well to come from two down to get into a winning position playing some very good football but then we have shot ourselves in the foot.
"We didn't defend well enough. We gave away two penalties and an own goal. No one is happy with that. Something has to change.
"Defending is all about the fine detail and the decisions you make. We can't keep doing this because you can't give goals away and win enough football matches to be where we want to be."
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