Arsene Wenger has revealed that full-back Bacary Sagna will not be fit in time for Arsenal's trip to north London rivals Tottenham on Saturday.
The Gunners, who sit in fifth place in the Premier League, travel to White Hart Lane on Sunday four points behind Spurs, who are in third, while fourth-placed Chelsea host West Brom.
Many have labelled the clash as a must win for Wenger's men, including midfielder Santi Cazorla, however the manager will have to do without his first-choice right-back who remains out with the knee injury that saw him miss the club's last match with Aston Villa.
"[Sagna] is not ready for Sunday," the Frenchman told the club's official website. "It is too short for him."
The 63-year-old also indicated that left-back Kieran Gibbs is still not ready to return from a thigh problem, while Abou Diaby, who is suffering from a calf complaint, will face late tests.
"Abou is an uncertainty," he added. "He has a calf problem, a minor one. It is question of days. He will have tests and then we will see if we can use him on Sunday or not. It is a 50:50. Actually maybe a bit more for him playing.
"Kieran is not back. That was as we expected."
Carl Jenkinson is expected to play at right-back, while Nacho Monreal should continue on the left. Meanwhile in midfield Aaron Ramsey could partner Mikel Arteta, or Jack Wilshere could may deeper with Santi Cazorla moving into the centre and Lukas Podolski starting on the left wing.
Arsenal will be looking to replicate the form that saw them defeat their bitter rivals 5-2 in the return fixture at the Emirates earlier in the season, although they were helped by an Emmanuel Adebayor red card.