Gareth Bale
Gareth Bale came off the bench to score the winner in the Fifa Club World Cup semi-final against Al Jazira. Getty

Real Madrid star Gareth Bale has admitted that he is still not ready to play 90 minutes ahead of the Saturday's [16 December] Fifa Club World Cup final with Gremio which will come only a week prior to the highly-expected El Clasico against Barcelona in La Liga.

The 28-year-old forward has been plagued by varying muscle injuries during the opening part of the season.

The Welshman made a return to action from a two-month spell on the sidelines during the recent Copa del Rey draw with Fuenlabrada on 28 November.

The former Tottenham Hotspur star created two goals for Borja Mayoral in that game but a day later it emerged that he had suffered a recurrence of a calf problem.

The Real star missed the next three games as a result before returning to action in Los Blancos' 2-1 victory over Al Jazira Club in the Club World Cup semi-final against on Wednesday [13 December].

Bale made an instant impact again after coming off the bench in the 81th minute to score Real's winner with his first touch.

The Welshman was delighted with his comeback but he suggested that the upcoming games against Gremio and Barcelona might come too early for him to make Zinedine Zidane's starting line-up against Cristiano Ronaldo and co.

"I need to build my fitness up. It's been a frustrating few months in terms of injuries. I need to be patient with myself. It's a long season. I hope to be able to help the team during the rest of the season," Bale said to Cope after the win over Al Jazira.

"No, it's just physical. It has nothing to do with my mind. It's just one of those times I am having a few problems. I have to be patience. I just need to work hard, I am doing it off the pitch to get myself back to full fitness and hopefully I can come back and be strong until he end of the season."

Real will attempt to defend their Club World Cup title against Gremio before returning to Spain to face Barcelona on 23 December in a clash which could be decisive for the La Liga title.

Pressed when he expects to be able to play 90 minutes again, Bale said: "I am not sure. I have to sit down with the manager. I need build my fitness as quick as possible."

Zinedine Zidane may only give Bale a handful of minutes against Gremio and Barcelona with the two games coming only before the La Liga Christmas break which will give the Real ace to rediscover full fitness ahead of the second part of the season.

"I need to be patient and listen to my body, I need to be playing because I'm not 100 percent. Little by little I'll be picking up the pace. I'm working hard on and off the pitch," Bale added to Marca.

"I'm happy to get the goal. When you come back from injury, you always want to make as much impact as I did tonight, but the best thing is that the team is in the final."