The headline statistic offers some insight. In the 12 games he’s been involved in, City have kept seven clean sheets. In the 19 other matches, Manuel Pellegrini’s side have kept two.
Statistics don’t always tell the whole story. The quality of opposition. Their form coming into the game. Injuries they suffered. These are all variables not captured by a straightforward figure.
But, clearly, with such an obvious pattern from a fairly large sample size, we can logically assume City struggle to defend as well when Kompany doesn’t play—his absence destablises them at the back.
Apart from last season, which was a disaster for Kompany from start to finish, the centre-back has been a beacon of consistency since his arrival from Hamburg in 2008.
He is strong and quick. He starts moves from the back because he has the confidence and ability to move into advanced areas with the ball at his feet. He is brave, committed and intelligent. At his best, he’s the finest defender in the Premier League.
But it isn’t just his raw attributes that make him such a quality player. His leadership and organization are perhaps what City miss the most when he is unavailable.
Which would explain the chaos that ensues when he isn’t on the pitch. City have had fleeting moments of solidity in his absence this season, but there have also been plenty of times they’ve looked completely disjointed, unable to even hold their line and defend as a unit.
Eliaquim Mangala perhaps embodies Kompany’s dramatic effect on the side. The first five games of City’s season saw the two of them paired. They kept five consecutive clean sheets and took 15 points. Mangala, who had looked decidedly nervous and, at times, incompetent during the previous season, suddenly looked to be settling into life at City.
But Kompany’s first calf problem of the season, sustained against Juventus in a Champions League group game at the Etihad, saw the Frenchman lose his way. His form has been erratic ever since, and he now has less than six months to save his City career.
Kompany returned and played for Belgium in mid-October, despite City suggesting he wasn’t fit enough, a situation that angered Pellegrini. He has suffered two further calf problems since.
During his brief spell being fully fit after playing for Belgium against the club’s wishes, he and Nicolas Otamendi briefly demonstrated they could form a solid pairing. Like Mangala, Otamendi’s best games this season have come alongside Kompany.
Where it leaves City is unknown. Kompany, 29, has plenty of time ahead of him, if, of course, the club’s medical staff can solve his calf problems. At the moment, that seems far away.
His last breakdown was perhaps the most worrying yet. After missing nine games, Pellegrini brought him on as a substitute against Sunderland. His comeback lasted just nine minutes, and he was taken off visibly distressed at his latest setback. A return date hasn’t yet been set.
It’s not overstating things to suggest City’s title hopes are resting on Kompany’s fitness. Without him, can anyone really see them finding the kind of consistency a title-winning side needs?
City possess plenty of quality, but without a stable platform on which to create they are unlikely to win enough matches to beat Arsenal to the title.
The importance of Kompany is huge.
Rob Pollard is Bleacher Report's lead Manchester City correspondent and will be following the club from a Manchester base throughout the 2015/16 season. All quotes were obtained firsthand unless otherwise noted. Follow him on Twitter @RobPollard_.