Roger Federer slumped to another early loss, with Gael Monfils beating him 6-4, 6-7 (5), 6-3 on Thursday in the third round of the Shanghai Masters.

Defending champion Novak Djokovic advanced to the quarterfinals with a 6-3, 6-3 win over Italian Fabio Fognini, while third-seeded David Ferrer of Spain was upset by Florian Mayer 6-4, 6-3.

Federer, who has slipped to No. 7 in the rankings, was playing for the first time since losing in the fourth round of the U.S. Open and was in need of a strong showing in Shanghai to secure his berth in the elite ATP Tour Finals — a tournament he hasn't missed since 2002.

The 17-time Grand Slam champion only has a slight lead over several other players vying to get into the eight-man field in London.