Florentino Perez believes that Real Madrid will once again see the "great" version of injury-plagued forward Gareth Bale and has explained the club's decision not to go ahead with a summer move for teenage sensation Kylian Mbappe.

Bale missed out on a Champions League reunion with former club Tottenham Hotspur earlier this week and manager Zinedine Zidane is unsure if the player will be ready for the return fixture at Wembley Stadium on 1 November due to a lingering calf problem suffered against Borussia Dortmund that saw him sidelined for Wales' final pair of pivotal 2018 World Cup qualifiers.

It is becoming an increasingly familiar tale of woe for the 28-year-old, whose 10 major trophy triumphs since joining Real Madrid for a then world-record fee of €100m (£89.8m, $118.3m) in September 2013 have been counteracted by 18 separate injuries.

He managed just 27 appearances across all competitions last term after requiring surgery on a long-term ankle problem.

Quizzed about Bale's constant injury issues during a lengthy interview with Spanish daily digital publication El Espanol, Perez admitted that the former Southampton prodigy was frustrated but backed him to rediscover his fitness and best form in a white shirt.

He also pointed to the long-standing left knee trouble that hampered former Galactico Kaka during the reign of Jose Mourinho in 2010 as evidence of a player at the very top of his game being ruined by injury.

"Things happen with players that we do not expect," the president said when asked if Bale's injury was causing him to lose sleep, as translated by ESPN. "Kaka came as a phenomenon, a Ballon d'Or. But he went to a World Cup, was given an injection, and returned with his knee destroyed.

"He was never the same Kaka again. Bale had a very big operation last year, was out for four months, and as Zidane has said, when you are out for so long you need the same time again, or even a bit more, to get your fitness back. I believe this period will pass. Gareth is a bit down about it, but very motivated to come back. We will see the great Gareth again."

Perez also admitted that Real did consider swooping for Mbappe during the summer transfer window, but claims it would have been tricky for Zidane to afford his compatriot the necessary playing time in order to further accelerate his astonishingly rapid development.

Big-spending Ligue 1 giants Paris Saint-Germain eventually agreed a one-year loan deal for Mbappe that includes an option to buy him permanently from Monaco for €180m next summer and Perez believes such a switch offers the 18-year-old the chance to fulfill his massive potential now.

"We thought about Mbappe [in the summer], but we have a very complete squad," he said. "It was difficult for us to fit in a young player like him, with a lot of promise. At PSG he will be able to play more often. He has a big chance to be a real star, as have our young players like Marco Asensio."