Birmingham City have signed midfielder Diego Fabbrini from Watford for £1.5m on a three-and-a-half-year contract.
Fabbrini, 25, has been on loan at Championship leaders Middlesbrough, for whom he scored six times in 24 matches.
The Italian spent two months with Birmingham last season, playing five Championship games, since when Blues boss Gary Rowett has been keen to arrange a more permanent deal.
He is now contracted to the club until the summer of 2019.
Fabbrini, who has one cap for Italy, began his career in his home country with Empoli and Udinese before coming to England to join Watford in 2013.
He is Rowett's third new signing of the January window following Sunderland winger Will Buckley, on an initial month's loan, and teenage midfielder Luke Maxwell, 18, from Kidderminster Harriers for £75,000.
In addition, Blues have extended striker James Vaughan's loan from fellow Championship side Huddersfield Town until the end of the season.
"I think Fabbrini is the last permanent signing we'll see in this window, which is why we've done it," said Rowett. "Now it's a case of trying to find a loan option. We've still got room for one full-back/centre-back/ defender who can play in a couple of position."
Blues remain up for sale, but had their bank balance boosted earlier this month by the sale of Demarai Gray, who joined Premier League side Leicester City for £3.75m.
After a run of 13 points out of a possible 15 since Boxing Day, Rowett's men are seventh in the table, below the play-off zone on goal difference.
Shane Lowry leaves St Andrew's
Birmingham City have cancelled the contract of Shane Lowry, by mutual consent, to allow the 26-year-old former Aston Villa defender to sign for Perth Glory in his native Australia.
The Australia international, who also played for Plymouth Argyle, Leeds United, Sheffield United, Millwall and Leyton Orient, initially arrived in September on a deal until the end of the season following a successful pre-season trial at St Andrew's.
He made just one start, in the 1-0 Championship win at home to Cardiff City, just before Christmas, also appearing as a half-time substitute in the 2-1 FA Cup third round home defeat by Bournemouth.
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