Bale is not certain to start for Real Madrid in Saturday’s showdown in Kiev, despite scoring five goals in four LaLiga games for the reigning European champions.
But Wales manager Giggs insists the 28-year-old has the right mindset to make a decisive contribution from the bench – if that is the role given to him by Real manager Zinedine Zidane.
“Every time Gareth plays he makes an impact,” Giggs said.
“It just shows the professional he is that he’s not sulking (when he’s a substitute) as he always seems to come on and score.
“He’s one of the best players in the world and every time he comes on to that pitch he makes a difference.
“Again that’s a credit to his professionalism, his hunger and desire to get in the team for that final.
“He will be thinking if he starts in the Champions League, great.
“But if he doesn’t, then he’s ready to score that winner anyway.”
A 13th European title for Real on Saturday would see Bale equal the record of Champions League wins, or its European Cup predecessor, by a British player.
Former Liverpool defender Phil Neal currently holds the record outright with four victories, and Bale would match that tally after five seasons in Madrid.
And despite having his critics in Spain, Bale has still managed to score 19 goals this season in an injury-hit campaign.
“Gareth always had potential, but he’s gone on to pass that potential,” Giggs said.
“He’s been playing at a top club for a long time where brilliant players have notoriously not lasted very long.
“He has been a huge success for club and country and one of the best British players to have gone abroad because of what he’s achieved.”