Midfielder Scott Arfield arrived from Burnley despite playing an important role for club this season while Allan McGregor has returned to his former club from Hull City to strengthen the goalkeeping position.
The 33-year-old also has global experience, having racked up 97 caps for Slovakia.
Allan McGregor has finalised his move back to Rangers.
McGregor has 38 Scotland caps and his form was rewarded with a recall from Alex McLeish recently.
The 38-cap Scotland global won three league titles, a hat-trick of Scottish Cups and five League Cup titles during his first Rangers stint.
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Rangers are expected to make a number of additions this summer as they look to try and compete with Old Firm rivals Glasgow Celtic and could also be expected to sell a number of key stars to fund those deals.
"I can't keep the smile off my face", McGregor told Rangers TV.
"I started training here when I was 12 years old and it's incredible to be back".
"I need to sit down with Steven and go through every single thing in detail, we're doing everything on the telephone at the moment because he's not here".
He joined Hull when they were in the Premier League and helped them qualify for the Europa League for the first time. However, he spent a season in Turkey before signing for Hull City in 2013.