Alexis Sanchez will not be ready to make his comeback from a hamstring injury in the FA Cup on Saturday, with Arsene Wenger saying the forward will be kept out of the team against Sunderland as a "precaution."
Sanchez has not played since injuring his hamstring against Norwich in November, but has been back in training this week.
However, Wenger said on Thursday that the Chile forward "is not quite ready" to return.
"It is a precaution because of his hamstring, and it takes a few more days," Wenger said. "He's not bad but he's not ready."
While Sanchez's absence limits Wenger's options in attack, captain Mikel Arteta is available after playing 45 minutes with the under-21s on Tuesday, his first game since injuring his calf in a loss to West Bromwich Albion in November.
With Santi Cazorla and Francis Coquelin still out with long-term injuries, Arteta's return is a boost to Wenger's depleted midfield as it starts the defence of its FA Cup title.
However, Wenger indicated he will not rotate his squad too much for the third-round game, despite the Premier League leaders having an away game against Liverpool coming up on Wednesday.
"The squad will be similar to the squad who played the last game against Newcastle. Will a young player or two start? I haven't decided yet," Wenger said. "The thinking is to give absolutely everything to qualify. We are the holders of the cup and I know as well by experience that it is very important that you get in the competition and that you have a successful third round. It's a tricky one, always, the third round."
Arsenal have not lost in the third round of the FA Cup since 1996. They can become the first team in 130 years to win the competition three years in a row.