“Gundo played just part of today’s session," he said at his pre-match press conference.
"We will see tomorrow how he feels.”
A muscular problem has kept the defender out for 15 games, with his last appearance coming in the Boxing Day win over Newcastle United, but he has started an individual training programme as he nears a return to full fitness.
“Nathan has come back to training on the pitch. Alone still, but he is closer to coming back with us,” added the City boss.
“The rest are fit.”
Both teams were in action in midweek, with Arsenal drawing 1-1 with Benfica in the Europa League the day after City had beaten Everton.
It means the Gunners have less time to recover ahead of Sunday’s meeting at the Emirates Stadium, but Guardiola says he is still expecting to face the best version of Mikel Arteta’s side.
“They will be fired up, physically ready and ready to compete with the best performance Arsenal can,” he explained.
“We know better than other teams in recent years perfectly how the schedule is. They will be on top.”
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