Celtic have signed Tottenham goalkeeper Joe Hart and former Crystal Palace midfielder James McCarthy.
Former England international Hart joins on a three-year deal while McCarthy has penned a four-year contract following his summer exit from Selhurst Park.
The Hoops will be hoping both men can have a positive impact on the squad after a difficult start to the season.
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On the arrivals, manager Ange Postecoglou said on the club's official site: "I'm delighted that we have signed two top-class players in Joe and James.
"Both of them have a wealth of experience at both club and international level and that is something which can only benefit the squad, and I'm looking forward to working with both of them.
"I know our supporters will be well aware of both players, and I'm sure they'll welcome them to the club and look forward to seeing both of them play for Celtic in the seasons ahead."
Sky Sports News reported Celtic's interest in Hart last week but talks had reached an impasse by the weekend.
But after constructive talks on Monday, the 34-year-old leaves Spurs for £1m with a year to go on his deal after making 10 appearances for Tottenham last season.
Postecoglou started the season with Greece international Vasilis Barkas, signed last year from AEK for a reported £5m fee, between the sticks but he has been replaced by Scott Bain in what is widely perceived as a problem position for the Parkhead club.
Hart, who has been capped 75 times for England, told Celtic's website: "This is a great moment for me in my career and I am absolutely delighted to be joining a club of Celtic's stature.
"I know just how big this club is and of the incredible support that it enjoys, and I can't wait to play in front of the fans at Celtic Park."
McCarthy returns to Scotland 10 years after leaving Hamilton following distinguished spells at Wigan, Everton and Palace.
The 30-year-old, who is a Republic of Ireland international, joins after two years at Selhurst Park.
On his move, McCarthy said: "To have signed for Celtic is a brilliant feeling and this is a special day for me and my family.
"I know all about the club, the size of it and all the success it's enjoyed, particularly in recent years.
"I'm looking forward to pulling on the Hoops, playing at Paradise and helping the team deliver more success to these amazing fans in the seasons ahead."
Postecoglou's side are preparing to face Czech hosts Jablonec in the first leg of their Europa League third qualifying round on Thursday.
Celtic have already been knocked out of the Champions League qualifiers by Danish side Midtjylland and lost 2-1 to Hearts at Tynecastle in their cinch Premiership opener at Tynecastle on Saturday night.
'An exciting move for Hart'
Sky Sports News' Michael Bridge:
"This is an exciting move for Joe Hart nearing the end of his career.
"Hart's future at Spurs looked bleak after the north London side signed Pierluigi Gollini on loan from Atalanta. Hart loves being at Tottenham but it's understood he wasn't in Nuno Espirito Santo's plans ahead of the new season. Alfie Whiteman has impressed in pre-season and is expected to be confirmed as Tottenham's third choice 'keeper.
"Hart featured in the Europa League and FA Cup last season but was never considered competition to captain Hugo Lloris.
"Despite rarely featuring, I'm told Hart was a highly regarded member of the squad and loved his time at the club.
"Hart is still in good condition but there will be concerns he's not played much over the past 12 months."
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