“Hazard broke the charts”: inside Chelsea’s ‘psychological coding’ project
‘They’re passing the ball with real confidence: you can just see how focused they are today’. It’s a line that could be taken from almost any commentator or pundit. It’s also a statement which fans across the world would recognise. We know when our team’s players are motivated. Or do we?
It’s a question that Malcolm Harkness, who was part of Chelsea’s backroom team for just under four years, has been wrestling with. Before leaving Cobham to take-up a role with Turkish club Trabzonspor, Harkness – working in partnership with his dad, Tim, Chelsea’s current Head of Sports Science – was responsible for ‘psychologically coding’ the London club’s games.
Recording ‘actions’ – such as a shot, pass or tackle – taken by both Chelsea’s first team and the opposition, Harkness would use a simple criteria to determine to what extent the ‘action’ displayed confidence, motivation or focus.
For example, a shot from outside the area which hit the target would be classed as a ‘confidence action’ and rewarded with a point. Likewise, a successfully completed through ball would see the player making the pass given a point for focus, whilst an attacking run made by a full back would be seen as a demonstration of motivation.
“For the last few decades, you’ve had loads of statistics, measuring possession, number of passes and number of shots, but I don’t think anyone’s really looked too much into the number of psychological actions”, says Harkness.
“When you code between 10 and 20 games, you start to see a lot of patterns emerging and get some really interesting insights into the players.”
Harkness and his father setup the project in late 2018, during Maurizio Sarri’s sole season in charge of Chelsea. The campaign was also notable for being Eden Hazard’s last at the London club and, unsurprisingly, the Belgian figured prominently in Harkness’ coding.
“Before he left, Hazard broke the charts every time. In every game he played, he made everyone else look like they’d done nothing for the whole game,” says Harkness.
Whilst Hazard’s confidence, focus and motivation were hardly questioned during a sparkling season, which he crowned by scoring two goals in a Europa League final win against Arsenal, Harkness, who would spend up to five hours coding a single game, uncovered some more nuanced results.
“There would always be little things that you weren’t expecting, like a player who just by watching the game, you think didn’t play so well, but made a lot of confident actions,” says Harkness.
“Callum (Hudson-Odoi) would come off the bench and be very effective. He would come in with a lot of confidence, drive the intensity of the game and give confidence to the other players.
“With N’Golo Kante, we would see a lot of focus actions, such as anticipating and intercepting a pass. It looked as though he was just in the right place at the right time, but he was concentrating so hard.”
Whilst Hudson-Odoi and Kante were emblematic of the confidence and focus rewarded by Harkness’ coding, Christian Pulisic was a stand-out performer when it came to motivation.
“Christian would record a lot of motivated actions through pressing. He’s a very fit guy and he would use that to put pressure on the defence and drive the whole press of the team. He would go to the right back, then the centre back, then the goalkeeper and end up on the other side of the pitch.
“That shows motivation because he doesn’t have to do that. The reason we’re giving him the point (for a motivated action) is because he doesn’t have to do it, but he does.”
Highlighting the project’s findings to a coaching team already immersed in data from different departments proved challenging, but, during an interview on The Football Psychology Show, Harkness was philosophical about the hurdles associated with working for a Premier League team.
“Petr Cech was very involved in the project and I think he found a lot of value in the data we gave,” says Harkness.
“Working at a top-level club like Chelsea, it’s sometimes tricky to get your say. You don’t want to act like you’ve got the most important information because you’ve still got a whole analysis team, GPS data and the medical department to think about, but that’s just part of the challenge of working for a big club”.
According to Harkness, who picks out Adama Traore as an opposition player who scored a high number of ‘confidence action’ points, the project was paused following his move to Turkey, due to pressure on Chelsea’s sports science resources.
However, with players’ interest in data, such as measurements of their top speed and distance covered during a game, now firmly established, Harkness believes that there could be demand for information on psychological performance.
“All the players have a lot of interest in the (GPS) data…after each match, we would put a visualisation up on the TV where they put their boots on.
“It would display their max speed, distance covered and that stuff, and they’d really get involved and ask questions. Of course, they get very competitive with each other: Tammy Abraham was very competitive with his max speed.
“Like the GPS data, in the future I think there might be a lot of value in a player – who’s interested in it – looking through the (psychological coding) data and maybe seeing where he’s not getting as many actions as another player in the same position or he’s getting a lot more.”