Celtic have signed defender Jack Hendry and goalkeeper Scott Bain from Premiership rivals Dundee.
Dundee say the undisclosed fee received for Hendry is a record for the club; while Bain joins Celtic on loan until the end of the season.
"I'm absolutely delighted to have signed for Celtic. Joining the Scottish champions is a brilliant move for me," Hendry told his new club's website.
Bain added that he was delighted to join the biggest club in Scotland.
On a busy evening of transfers as the window closed, Scott Allan joined Hibernian on loan from Celtic, via a spell at Dundee, while Hibs striker Simon Murray moved the other way to Dens Park until the summer.
Celtic were seeking goalkeeper cover following a knee injury to Craig Gordon, 35, ruled him out for about 12 weeks.
Bain, 26, joined Hibs on loan earlier this month but has not featured for Neil Lennon's side and was allowed to move on.
'Repay the faith shown in me'
Hendry, 22, who has signed a four-and-a-half-year deal, said: "I know, from playing against Celtic this season, the quality of players that are at the club and I can't wait to start training with my new team-mates," said Hendry.
"I also know that working with Brendan Rodgers and the rest of the coaching staff here will improve me as a player and I'm looking forward to working hard every day to repay the faith they've shown in signing me.
"I've already experienced playing at Celtic Park as an opposition player, but I can't wait to run out wearing the Celtic jersey and play in front of the Celtic supporters."
Bain, 26, said he was still coming to terms with his move to the Premiership leaders.
'My Dad was buzzing'
"I phoned my dad earlier today just to say that I was leaving Easter Road and on the road to Glasgow, and he was buzzing and delighted for me. I can't believe I was on the bench for Hibs against Celtic last weekend and then, just a few days later, I'm signing for Celtic.
"It's not something that, when I went on loan to Hibs, I thought was ever going to happen, so the past few days have been great, and to get it over the line and be here is absolutely amazing."
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