Inter: the numbers show Barella’s dip in form, but his post-derby comments are more concerning

Barella had a derby to forget. His average match rating was no higher than 4.5, with critics describing him as "out of sorts", "slow" and a player who "takes too many touches".

Across all three AC Milan goals, Barella does something uncharacteristic. For the first, he walks back and arrives too late to help the defence deal with the cross that Pulisic rises to head. For the second, Rabiot sets off from his position and Barella lets him pass as though he poses no danger. For the third, Barella recklessly tries to carry the ball out of defence, loses it and commits the foul on the edge of the box from which Moreira scores.

Barella's key statistics have fallen sharply compared with last season, a particular concern for a player with his attributes. The former Cagliari player is one of the best midfielders in Italy when he is fit and can perform at his explosive, mentally sharp best.

Despite signs of decline last season, Barella covers the same average distance per match as he did then. His average sprinting figure, though, has almost halved (13.7 versus 7.8).

His average tackles per match have dropped (1.6 versus 1.1), as have his ball recoveries (4.9 versus 4.3). He has also made 2 errors that have led to an opposition goal, compared with 0 last year.

In possession, he loses the ball more often (12.2 versus 11.9 times per match), while his key passes and cross accuracy have fallen slightly. Above all, his expected xAssists, the attacking potential of passes that could set up team-mates, have plummeted from 6.62 to 1.74.

Barella is playing at a slower pace than in the past two seasons. He poses less of a threat and probably needs a few more games' rest.

More worrying is the possibility that his biggest problem right now is mental as well as physical. His words to Sky and DAZN after the match offered the clearest warning sign.

"Since the start of the year, we've lacked the right attitude. That's a negative, though we've also shown our strength in second halves. But not every match is the same. Fatigue takes its toll. We have to be honest with ourselves. For some time now, we haven't approached the derby in the best way. Being the stronger side isn't enough, and we've been the stronger side before without winning. 

Not having fresh attacking substitutes on the bench probably influenced the manager's decisions, and we tried to do something different, perhaps losing our sense of certainty in the process."

Alessandro Bastoni was the first key player in the squad to speak so bluntly, saying ahead of the Champions League match against Shakhtar: "Champions League finals are a long way off; let's keep our feet on the ground." Chivu then said before a match: "If we haven't won a derby for a while, we need to ask ourselves why. We need to go back to being more provincial."

Today, it was Barella's turn. His words came after a thoroughly poor individual performance, though, and sounded more like an outburst than self-criticism. It was a communications own goal, much like the one Gleison Bremer scored a few weeks ago that triggered a mini-crisis at Juventus.

His dig at Chivu and the dressing-down he gave his team-mates over their attitude are the most serious warning signs for this team. More than the many poor starts or the matches they failed to turn around, it is the lack of unity of purpose that matters. The Romanian manager confirmed as much after the match: "We're lacking a bit of hunger."

Inter remain very much in contention on every front in a season that is far from lost. If they want to get going again and turn things around, this is surely where they must start.