Celtic have completed the signing of left-back Greg Taylor from Kilmarnock for an undisclosed fee on a four-year contract.
Taylor completed his medical with the Scottish champions on Saturday but the deal was thrown into doubt on Monday as all parties attempted to complete the transfer before the midnight deadline.
The Scotland international trained with the national team on Monday afternoon before a breakthrough was made between the two clubs.
He arrived at Parkhead to finalise his move on Monday evening.
"It's been a whirlwind of a day but I'm over the moon to be here and thankfully that's it over the line," Taylor told the club's website. "As soon as I knew of Celtic's interest, I was desperate to come, so it's been a great day, certainly now that it's done.
"It's a massive club, everyone knows that, and I'm here to win trophies, it's as simple as that and I can't wait to hopefully be a part of it. I'm delighted to be a Celtic player, and I want to try and impress the fans, and obviously the manager.
"A club this size wants to win trophies and they have done over the past few years, and now that I'm here, I want to help the team win more trophies."
The 21-year-old made his Kilmarnock debut in 2016 and played 41 times for the Ayrshire club last season.
Taylor is Neil Lennon's ninth summer signing after Celtic completed loan deals for Fraser Forster, Moritz Bauer and Mohamed Elyounoussi.