Liverpool agreed a late deal for Japanese winger Takumi Minamino to go on loan to Southampton for the rest of the season.
Discussions over a move began on Monday morning, with an agreement requiring a deal sheet to be submitted in order to complete the arrangement after the 11pm deadline had passed.
Minamino has not joined in time to be included in Southampton’s squad to face Manchester United on Tuesday evening but should be available for Saturday’s match against Newcastle United.
Southampton manager Ralph Hasenhuttl said: "I am very pleased to welcome Takumi to our squad for the rest of this season.
"He will help provide another good attacking option, and is importantly the right profile of player for us.”
Meanwhile Everton have added Josh King on a permanent basis after beating fellow Premier League side Fulham to the Bournemouth striker.
The 29-year-old Norwegian international was out of contract at the end of the season and joined for a nominal fee.
Fulham instead signed striker Josha Maja on loan from Bordeaux, with an option to buy for around £9 million.
For a full rundown of the deadline day deals across the major European leagues, plus links to club-by-club ins and outs throughout the January window, click here.