Middlesbrough overcame a late complication to complete the signing of Gary O'Neil from Portsmouth less than an hour before the transfer deadline.
Gareth Southgate targeted the Portsmouth player after being handed the reins at the Riverside Stadium last summer, but had to wait until this week to make the breakthrough.
The 24-year-old underwent a medical on Teesside on Friday afternoon after the two clubs agreed a £5million fee (€7.3m).
Southgate told Sky Sports News: "We've just completed the deal, we've very pleased and I'm looking forward to getting home to bed!
"Gary had an injury before the end of last season and had a little operation, so we needed to be sure everything was okay with that and that's why there was a delay earlier in the evening.
"He's our player now so we're really chuffed."