Former Celtic Beram Kayal admitted the Rangers pulled off a coup in Leon Balogun.
Gers boss Steven Gerrard caught 32-year-old Bosman on Friday to cover the injured Nikola Katic.
It’s been a massive season for Rangers as they try to end Celtic’s attempt for 10 in a row and cover from the Croatian center-back was vital.
Balogun, whom Kayal has known since their time at Brighton, has 32 caps for Nigeria despite being born in Germany.
And the former Celtic star has said his former club’s Old Firm rivals have made a choice addition here.
Kayal told the Glasgow Evening Times: “Leon is a very good center-back. I rate it very high. He’s excellent on the ball and has presence. He has a lot of dynamism, physique and technique. It is perfect for Scottish football.
“He’s a great professional. He always does extra work on his game on the training ground. He’s a good guy too. He’ll be a great character for the Rangers in the locker room.
Kayal spent five years at Celtic before leaving for the Seagulls in 2015.
And the Israel international, who was signed by Neil Lennon in 2010, is extremely confident his former blunderer will stage a 10th successive Premiership title at the expense of Rangers.
He added, “Neil Lennon is a great guy, he’s hungry, he wants to win. I’m confident Celtic will do it.
Celtic will kick off their Premiership title defense next Sunday with a visit to Hamilton, a day after Rangers visited Aberdeen in a tough first game for the Ibrox side.
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