Petr Cech's 209 clean sheets represent over 300 hours' worth of games in which a goal was not conceded, but that is equivalent to just a fraction of the time spent by our goalkeeper on the training, analysis and preparation that helped him break the club record at the weekend.
For an insight into Cech's work during his nine and a half years at Chelsea, and what the clean sheets mean to a goalkeeper, the official Chelsea website turned to the two men who have worked as the goalkeeper coach during that time.
Christophe Lollichon (pictured above right) knows Cech and his football as well as anyone, having coached the player during the two years he was with Rennes in France prior to his transfer to London, and then having reunited with him at Chelsea in 2007.
He considers just how important a clean sheet is for a goalie.
'The first thing a goalkeeper wants, and for Petr this is definitely the case, is to win,' says Lollichon.
'But if he doesn't concede a goal it is a good bonus because I don't know one goalkeeper who likes to concede a goal.
'I remember a game when we were winning 3-0 and it was not very difficult and in the last minutes we conceded a goal and Petr was so upset, and so was I on the bench because 3-1 is not like 3-0. He came into the dressing room saying it is impossible to concede this goal, and that is normal because Petr is a perfectionist and for him, 3-0 is a lot better than 3-1.'
Lollichon is keen to make clear that the clean sheet record represents achievement and quality on several levels. It shows the special talent Cech possesses but also the talent throughout the club where he has been first choice since joining in 2004.
'Every time there is a clean sheet it means a goalkeeper didn't concede a goal but it is not only the goalkeeper, first of all there is the team,' he says.
'We are very proud of this record and Petr is very happy. Every player likes to beat records but it is not only the goalkeeper.
'We have a good chance to keep clean sheets because of the quality of the team and because of the quality of our goalkeeper. There will be other teams in Europe with a good percentage of clean sheets but the difference is we play in the Premier League and it is not the same, it is hard not to concede goals here.
'I remember one game against Bolton we were winning 4-0 and then it was 4-3! This is one of the reasons why I love this football, and Petr's 46 per cent clean sheet record is a very good performance because we play in the Premier League.'
For Cech's first three seasons at Chelsea after he moved from Rennes, the goalkeeper coach was Silvino Louro (pictured below), who returned with Jose Mourinho this season and is now an assistant first team coach.
He recalls the choice between Cech and Carlo Cudicini for the first match of the first Mourinho era in August 2004, and what proved to be the first of the 209 clean sheets.
'It was difficult because Carlo Cudicini was one of the best players in the league,' says Silvino.
'But after Petr started training, Jose Mourinho liked him and put him in for the first game against Manchester United and we won 1-0. He caught the first cross and went on and had a fantastic game, and the decision was made.'
Included in that first Chelsea season was a Premier League run of 1,024 minutes without a goal conceded which added 10 clean sheets to the Cech total. By the end of the campaign he had a championship medal plus records for the fewest goals conceded and most clean sheets in an English top-flight season.
'That number of minutes without conceding is a compliment to Petr,' notes Silvino, 'but I believe he always wants more, more, more minutes.
'Only 15 league goals were conceded that season, and we didn't lose any games at home. I will never forget his first year at Chelsea. After the win at Bolton to win the league, the supporters were very happy.
'At Bolton he had a fantastic game, and before that at Blackburn there was a fantastic save from a penalty when we won 1-0. I remember games against Liverpool and Manchester United too, but my main memory is of Bolton. I will never forget it.'
A second Premier League title was won in 2005/06 but early on in his third year, Cech suffered the fractured skull injury that brought his outstanding career to a shuddering but thankfully temporary halt. He returned just three months later and almost immediately added six clean sheets in a row to his club total.
'Petr's recovery from the injury was incredibly rapid,' remembers Silvino. 'He was very strong mentally, to come back so quickly was difficult. In his first game you would expect him to be a little nervous of the first contact, it could be dangerous, but soon we all saw he was very confident and after that it was good.'
Such was his recovery that Cech has remained unquestionably the first choice for club and country. The trophies have continued to be lifted at Chelsea and in 2011 he was named the club's Player of the Year. Lollichon by now was the goalkeeper coach.
'I think Petr could have won the Player of the Year a lot of times,' he says.
'His level is regular and that is one of the most important qualities we need for a goalkeeper, the consistency. If the goalkeeper has five fantastic games and makes a lot of saves but in the sixth he makes a mistake, and then five fantastic games again and the next bad, for me that is not a top-level goalkeeper. And Petr is at the top for a long time.
'A keeper can be a guy who makes fantastic saves but Petr's focus is also tactical, technical, physical and because he is a perfectionist, he analyses everything to be performing for the team, not just for himself.
'He had a very good season in the Champions League-winning season and also last season, when he played 63 Chelsea games and seven international games. To stay performing like he did last season, sometimes the physical training had to be less and we did other things, small exercises or analysis.
'We had to feel the moment, and sometimes we asked him to work more and sometimes that was impossible. But I know Petr is intelligent, he can manage his life, and I have to help him manage his professional life and we have a very good understanding.'
It is an understanding forged from more than eight years working together and Lollichon compares the young keeper he coached at Rennes with the record-breaking one of today.
'Now he has more experience because Rennes is a good French club but it is not a top European club, and with Chelsea we play a lot of big games - finals, Champions League almost every year, and when you have his talent and you play at a big club, it is this combination that makes you at the top level.
'But we still analyse his games like we did when he played for Rennes, and every time he wants to understand what happened, why he conceded a goal. At the age of 31 he still wants to improve and become more perfect if it is possible, which for the goalkeeper coach is fantastic.'