Watch: Roger Federer's message to Rafa Nadal post Australian Open 2018 injury setback

Melbourne: World number two Roger Federer said that he wished Rafael Nadal well after the Spaniard retired from his Australian Open quarterfinal against Marin Cilic with a leg injury.

Read: Rafael Nadal out for 3 weeks post quarterfinal loss against Marin Cilic in Australian Open 2018

The 36-year-old tennis ace revealed that he sent a message of goodwill to the world number one.

After his quarterfinal win over Tomas Berdych at Rod Laver Arena on Wednesday, Federer said he sent a text message to Nadal before he went to sleep, adding, "I'm happy the news is not terrible. It's not nice to see fellow rival and friend go out like this."

Nadal had to withdraw in the fifth set of his quarterfinal with Cilic.

Federer added, "At this point, I wrote Rafa late last night before I went to bed, it was the last thing I did. I was like "right, I've got to write to Rafa and see how he's doing and that I hoped he was going to be ok with the scan today. I wish him well."

The Swiss maestro, who beat Nadal in last year's final at Australian Open, also commented on his rival's new look for this year's Australian Open - a sleeveless shirt similar to the one Nadal used to wear in his teenage years.

He joked that he can never pull off the look himself in court.

Meanwhile, Federer won his quarterfinal match against Tomas Berdych and reached his 14th Australian Open semifinal with a straight-sets victory 7-6 (7-1), 6-3, 6-4 in the Rod Laver Arena.

Federer will now face unseeded 21-year-old Hyeon Chung of South Korea in the last four on Friday.