For the defense and goalkeeper, there is nothing better than a clean sheet. That amazing feeling of knowing that the other team could not score against you. After the Burnley match on September 18, Ben White stated:
I think clean sheets are really important. If you get that, you've got a good chance of winning. We've got the quality up front so if we're keeping a clean sheet, we're always going to win a game.
Sometimes the clean sheet happens with luck, sometimes it happens by playing well. Arsenal, like most teams, have experienced both on their way to victory. With better finishing, Brighton could easily have scored in matchweek 7. Without the heroics of Aaron Ramsdale, Leicester would have scored in matchweek 10. As it happens, both matches went down as clean sheets for what has become a stingy defense.
In the first three league matches, Arsenal scored zero goals and their opponents netted 9 times. We will no longer speak of such things and pretend the league season started with matchweek 4. Since then Arsenal have allowed 4 goals in 8 matches, keeping 5 clean sheets. As Ben White summed up so poignantly, if the opponent does not score, you are more likely to get the three points. You certainly cannot lose!
At the time of writing this Chelsea and Manchester City are leading the league in clean sheets with 7 in 11 matches. Liverpool has 6, and Arsenal is tied with Southampton at 5. So you have four of the top five clubs in the Premier League also in the top five of team clean sheets. If you were wondering, West Ham is the outlier of the top five with only 3 clean sheets.
Unsurprisingly, it means the more clean sheets you keep the more likely you are to be near the top of the league table. It is not easy to score multiple times in a match against top competition, so keeping the opposition out of your net is imperative in order to take all three points. Relegation teams usually will average less than one goal a game over the course of season. Mid-table clubs in the Premier League will average around 1.5 goals per game. Top clubs will make it to 2 goals per match. The historically prolific Manchester City squad of 2019-20 reached nearly 2.7 goals per match!
Wondering about the undefeated 2003-04 Arsenal team? Only a paltry 1.9 goals scored per match. However, that was the best scoring tally in the Premier League that season. Their defensive record was also the best, allowing only 26 goals in 38 games. Breaking news! If you score the most goals and allow the fewest goals, you are more likely to win the Premier League title.
Since 2003-04, the following teams have done the same thing:
2005-06 Chelsea - 1st place
2007-08 Manchester United - 1st place
2011-12 Manchester City - 1st place
2013-14 Manchester City - 1st place
2017-18 Manchester City - 1st place
2020-21 Manchester City - 1st place
Besides concluding that Manchester City has been annoyingly good these past 10 years, we can definitively conclude any club that scores the most goals and concurrently allows the fewest goals will win the Premier League that year. A team of data scientists was not needed to parse this research question.
But how did the Gunners and the teams listed above fare those years in terms of clean sheets? For 2003-04 Arsenal, Jens Lehmann tied with Edwin van der Sar for the league lead with 15 clean sheets. As a team, Arsenal’s 15 clean sheets was second to Chelsea’s 21. Their record in “clean sheet” matches that year was 11 wins and 4 ties. That is right, four matches that ended in 0-0. For the others, here is the info:
2005-06 Chelsea - 20 clean sheets - 2nd most
2007-08 Manchester United - 21 clean sheets - tied for most
2011-12 Manchester City - 17 clean sheets - 2nd most
2013-14 Manchester City - 16 clean sheets - 3rd most
2017-18 Manchester City - 18 clean sheets - 2nd most
2020-21 Manchester City - 19 clean sheets - most
So not only is it good score the most and allow the fewest, it is also good to keep the other team out of your goal altogether. Just for the record, Chelsea had an astounding 25 clean sheets on their way to only allowing 15 goals in the whole 2004-05 season! Basically, if you cannot keep a clean sheet, the club needs to limit the opposing club to one goal. It is a terrific recipe for success. Bet you never thought of that.
There is the occasional outlier, (1) the team that does well at keeping clean sheets but still finishes lower in the table or (2) the team that has a harder time keeping a clean sheet but still finishes closer to the top of the league. The general rule remains: the more clean sheets, the better the position at the end of the year. There is correlation, even if it is not causality.
So how is Arsenal doing this year in relation to this statistical relationship? Great question…which I will answer in part two coming soon.