Drogba has struggled for consistency and fitness this season, but showed glimpses of his best in the 1-1 draw with Tottenham last weekend, even though he missed a last-gasp penalty.
The Ivorian was denied the chance to continue his return to form when Sunday's clash with Manchester United was postponed, but Ancelotti believes the 32-year-old will be ready to fire when he faces Arsenal in a week's time.
He'll be back: Drogba is tipped to return to the top of the scoring charts
He told his club's official website: 'We need Drogba to come back to the performances he had last year and the goal against Tottenham was very good for his attitude.
'I understand he has not been in a good condition. He had difficulty to play with malaria, he was tired, he was not 100 per cent and he found it difficult to train.
'I put him in the last few games even though he was not 100 per cent because we need to have his character and his personality.
'Now his condition is better. He had a good reaction after coming on as a substitute in the last game, this is the important thing and following the goal against Tottenham he will show us a different Drogba in the next game.'
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