A Juan Mata free-kick and an Alex Sandro own goal helped Jose Mourinhos side breathe new life into their Champions League campaign and inflict upon the Old Lady their first defeat in any competition since April.
Chelsea are two points behind current Premier League pacesetters Manchester City but are yet to lose a competitive fixture this term, unlike Pep Guardiolas troops who suffered a surprise home defeat at the hands of Lyon back in September.
All told, Chelsea have gone 16 games without defeat in all competitions and put their proud record on the line against BATE Borisov in the Europa League on Thursday.
Despite his recent run of good form, Alvaro Morata has not travelled with the squad, but Eden Hazard could feature after making a decisive cameo in Sundays win over Crystal Palace.
Explaining his squad selection, Sarri said: Morata stays at Cobham just to rest because he played very often in the last period, and just to have training.
So I think that its better for him and more easier to stay fit with two or three training sessions than only with matches.
So I think its normal for a player to play three or four matches and then rest. Otherwise, we can have a squad with 13 or 14 players.
Sometimes its better to actually rest than always play. Sometimes the players need to train on some specific things, to work on physical qualities, instead on other things they dont have to.
Sometimes its better this than actually playing. If they only play, they will lose that physical quality that they need. This is proved scientifically. In 21 days.
On Hazard, he added: For our doctor, there is not any risk otherwise he would have stayed in Cobham, of course.
We thought that, for him, its better to him. Not for 90 minutes, but to play after two weeks without playing.
So, in the last match, he played only for 30 minutes. For us, the best work for him is that he will play for 45 or 50 minutes tomorrow.
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