The GK xG model shown above looks at every shot faced, pass received, cross faced & through ball faced & calculates the probability of a goal occurring for & against the GK’s team before the event & after the event occurs!
Thus it measures & evaluates every action a GKs makes!
This allows all GKs to be given a single number measured in goals called
“Total Value in Goals”
Which describes the GK’s value to their side vs having a league average GK & takes into account everything they do meaning GKs of vastly different styles can be fairly compared!
Loads more information & content will be coming out on @goalkeeper_com about this model & statistically analysing goalkeepers in general so stay tuned!
For those interested in #DeGea, he is performing below #PL average standards due to 3 factors:
• His shot stopping mistake against #Brentford
• His cross claiming mistake vs #Brighton for the 1st goal
• His generally poor passing & giving the ball away in his own half
For those interested in #Mendy, he is performing below #PremierLeague average standards due to 3 events:
• His ball playing mistake vs #Leeds
• His shot stopping mistake vs #Leicester
• When he was beaten by a weak header vs #Southampton & it was cleared off the line
When receiving the ball under pressure, both #Chelsea GKs have been below the #PremierLeague standard!
#Mendy has cost #CFC 0.52 xG more than the avg #PL GK would be expected to if they received the ball in the same situations (this is heavily influenced by his mistake vs Leeds)
Similarly #Kepa has cost #CFC 0.59 xG more than the avg #PL GK would be expected to if they received the ball in the same situations as he did in his last 15 #PremierLeague games, #Kepa’s numbers here are heavily influenced by his mistake vs #Liverpool which #Mane capitalised on!
A GK’s handling ability is vital & often under analysed!
Here #DeGea showed how handling can determine a game’s outcome when he parried a 49mph central shot into danger & the rebound was scored!
xRebound xG = 0.09
Actual Rebound xG = 0.47
xG added due to poor handling = 0.38
My handling model uses historic shot data to gauge how often certain shots should be expected to be caught, parried away from danger, & parried into danger in combination with a none shot xG model which assesses how likely rebounds are to be scored based on the parry location
My model found that due the shot’s lower than avg velocity & central trajectory an avg PL GK would expect to parry the ball into an area which resulted in a goal from the rebound only 9% of the time whereas #DeGea pushed it into an area which results in a goal 47% of the time!
My 1v1 model also finds the smother to be very vulnerable when the 1v1 is central as it often allows the GK to be rounded or chipped plus it does very little to cover the side the GK does not have their hands!
A spread wouldn’t drastically increased the Rambos save probability!
His decision making is good, as he doesn’t engage too soon & only engages once he cannot to react in time to the shot, but his problem is, as always, the way he twists his body away from contact which leaves gaps in his barrier!
My model finds that if #DeGea had engaged the 1st touch the chance would’ve been 0.64 ExG because even though the 1v1 is quite far from goal engaging in that location would make the GK very vulnerable to the chip, sidefoot finish, and being rounded.
Engaging the 2nd touch, as #DeGea does, means the chance is actually 0.42 ExG as even though the 1v1 is closer to goal when the GK engages here there is usually very little space to exploit over, through, or round the GK!
Today I’ll breakdown #DeGea’s performance in the #PremierLeague using my bespoke GK models!
The headline is for the first time in 3 seasons #DeGea’s shot stopping skills are outweighing his weak shot prevention skills & thus far he has saved #MUFC ~5 additional goals!
Shot Stopping:
#DeGea’s shot stopping has been world class, my model predicts he has saved #MUFC ~5 goals more than an average #PL shot stopper would’ve thus far!
The goalmouth map highlights just how hard #DeGea has been to beat, if you don’t hit the corners you won’t score!
Shot Stopping:
His Best 3 Saves (Lowest ExSave Saves Made) are below 😮:
1. 24% Save Probability vs Jesus
2. 34% Save Probability vs Almiron
3. 42% Save Probability vs Pukki
They highlight #DeGea big strength, his reflexes & ability to cover huge amounts of the goal area.