Melbourne: Swiss star Roger Federer has reportedly been confirmed as a `surprise` teammate of his compatriot and newly-crowned Australian Open champion Stanislas Wawrinka for the Davis Cup World Group tie in Serbia.

Although the former world number one, who has slipped two places to eighth in the latest ATP rankings, was omitted from Switzerland`s original team sheet, his presence on the hard indoor courts of Novi Sad was confirmed by competition organisers.

According to Sport24, new world number three Wawrinka posted a photo of himself and the 17-time Grand Slam winner with the caption, saying `Look who I`ve found in Novi Sad `.

The report mentioned that the Davis Cup is the only major trophy missing from Federer`s sideboard and this is a rare first round appearance for Federer after his 2012 appearance when Switzerland was brushed aside 5-0 by the United States on home clay.

Serbia, who lost in last year`s final to the Czech Republic, are themselves without world number two Novak Djokovic, the report added.