Joey Barton of Rangers
Rangers signed Barton on a free transfer following the departure of the former Newcastle United midfielder from Burnley at the end of the 2015-16 campaign.
The Gers also secured the services of former Tottenham Hotspur attacking midfielder Kranjcar in the summer transfer window.
Barton and Kranjcar are high-profile signings and are expected to make Rangers competitive in the Scottish Premiership this season.
Former Rangers and Blackburn Rovers defender Hendry understands the reasons for signing the duo, but he has asked whether or nor succeeding at Ibrox matters to them.
Rangers' Joey Barton in action with Dean Marney
“Barton and Kranjcar are good signings,” Hendry told The Scottish Sun. “You have to ask the question if they are, well, not over the hill, but have had too much over their careers to worry about going to Rangers and being a success. We’ll find out."
Niko Kranjcar at Tottenham Hotspur
Rangers kicked off their 2016-17 Scottish Premiership campaign with a 1-1 draw with Hamilton Academical at Ibrox earlier this month.
Mark Warburton’s side then got the better of Peterhead 5-0 at Ibrox in the second round of the Scottish League Cup.
The Gers defeated Dundee 2-1 away from home at Dens Park in the Scottish Premiership at the weekend.