Roger Federer plans only a one-match appearance in doubles play Friday at the Laver Cup before making his retirement from tennis official.

Federer said Wednesday in London that Laver Cup officials agreed to allow him to appear in a match of his choosing, altering rules of the event to grant Federer's wish for the final sendoff.

"I know my limitations, and this is why I asked (European captain) Bjorn (Borg) if it's OK that I play just one doubles," Federer said. "I guess that one would have to be Friday night. So here I am, trying to prepare for one last doubles. We'll see how it is. I am nervous, because I haven't played for so long. I hope it goes well."

Federer would love to have Rafael Nadal by his side for that match.

"I think it could be quite a unique situation, if it were to happen. For as long as we battled together, having had always this respect for one another, our families, coaching teams, for us as well to go through a career we both have had, come out the other side and have a nice relationship, is maybe a great message to tennis and beyond," Federer said. "For that reason, it would be great, I don't know if it will happen, but it would be great."

Federer's slot Saturday and Sunday would go to 26-year-old Italian Matteo Berrettini.

The Laver Cup format requires players to participate in singles and doubles matches in scoring that pits European players against competition from the rest of the world.

Federer announced the London event would be his last in competitive tennis, allowing that his surgically repaired right knee wasn't responding as hoped and his body was feeling its age -- 41.

But the 20-time Grand Slam winner said the extended break from the court has given him time to add perspective to his accomplishments.

"To become one of the most consistent players ever is quite a shock to me as well," Federer said. "That is a great accomplishment for me personally, that I was able to stay at the top for so long. There are so many things I will miss; the fans are at the center of everything. I will miss that, every interaction on the court and off the court."

--Field Level Media