
The newly-promoted Blues started their Premier League campaign with a bang, substitute Jack Clarke scoring a last minute winner, but two key men were absent.
On Philogene, who is set to be a key figure despite a summer of speculation regarding a possible exit, O'Neil explained: "Sorry, I should have mentioned him yesterday when I said everyone was okay.
"He hurt his ankle in the Berlin game, so we'll review him again this week. We don't know how long he's going to take. He had a little nick on the ligament from the Berlin game, so he was unavailable."
On midfielder Florentino, a £16m summer signing from Burnley, he said: "Hopefully back with the group this week. He felt his calf after the game he played here against Vallecano. We thought it was not too much, but it's taken a little while to clear up. We were hoping he'd make today, but he just misses it.
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"We definitely won't risk him on Tuesday (home game in the Carabao Cup), but we're hoping he'll be around for Manchester United (away next weekend)."
Julio Enciso limped off in the second half of this game after producing an electric second debut for the Blues.
"Just cramp," confirmed O'Neil. "He'll be back on the grass on Monday.
"We've had three issues in pre-season and all of them have been for players who joined the group late - Julio, Florentino and Abdul Fatawu.
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"The pre-season that the fitness staff have put together for our guys has been exceptional. You can see how fit we are to still be pressing late on in the game.
"Some of the ones that have joined us late are just taking a little bit longer. Obviously we were desperate to play Julio today from the start but we've not seen much of him. We don't know exactly where he is physically.
"It's important that we try and get these guys up to speed without losing them."
Meanwhile, O'Neil revealed that Azor Matusiwa is 'close' to being available again having undergone post-season thigh surgery.
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