Jermain has missed the last three games with a muscle injury, Gareth damaged his ankle late in the Europa League quarter-final, first leg against FC Basel on April 4 while Aaron limped out of that match early with a hamstring problem.
"There are positive signs," said Andre. "Jermain has trained with the team all week and is showing excellent signs of improvement.
"Gareth has trained with the team in the last two days and he's made a great recovery, great work by the medical department.
"Aaron hasn’t trained with the team yet, he’s trained alone and we’re hoping to have him back for tomorrow’s training session, so he’s in with a chance."
William Gallas (calf), Younes Kaboul (thigh) and Sandro (knee) remain out.