Signed by Redknapp for £3.5m in the summer of 2006, he has become a hugely popular figure at Fratton Park.
But not everything has gone so smoothly in his career.
A teenage star with Dynamo Zagreb and a full international when barely out of his teens, he caused a Sol Campbell-like storm by signing for rivals Hajduk Split.
Current Portsmouth defender Campbell may have been criticised by Tottenham fans for moving to Arsenal in 2001 but Kranjcar's agent was murdered in an apparent mafia hit and the player also faced accusations of favouritism during his father Zlatko Kranjcar's time as national coach.
It is perhaps no surprise that he is enjoying life under Redknapp, who signed his own son Jamie at both Bournemouth and Southampton.
"Our relationship is great," said Kranjcar. "The players he has brought in are fantastic and we hope we can get to fifth spot and get to Europe.
"We are still in the hunt for the FA Cup, which is a massive achievement for Pompey, and it wouldn't happen if the manager wasn't as good as he is.
"When you see the quality of players I'm not surprised. We all knew we had a great group of individuals but we play well as a team and we have players who can finish a football match.
"Hopefully it will continue to get better until the end of the season. It has been a great season but it won't count for anything if we don't go all the way.
"You can say we made the semi-finals but knowing we have a great chance to win it we have to do everything in our power to go all the way."
A Pompey triumph may not provide the ultimate fairytale finale that a Barnsley or Cardiff victory would.
But for Kranjcar, who grew up watching FA Cup finals on TV in Croatia, it would be a fitting end to a season that has seen the rebirth of his own reputation.
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