SINCE his return to Ibrox, Allan McGregor has been in brilliant form for club and country. Whether it be helping out Rangers hold on for a result in Europe by pulling off a series of seemingly miraculous saves, denying last-gasp opportunities when playing in goal for the national team or making vital stops to secure points in the league, McGregor seems to always step up when he’s needed.
The 36-year-old has been one of Steven Gerrard’s most important signings this season and has excelled on his return to the club where it all began for the shot-stopper. McGregor’s excellent form has led some pundits to claim that McGregor is now the best goalkeeper in Scotland – but is this actually the case?
The most obvious place to look to see if this is indeed true would be to have a look at the amount of goals each Premiership keeper has conceded, and whoever has the fewest can be crowned the winner. As we all know, however, football is rarely that simple. Different goalkeepers play within different tactical systems, with defenders of varying ability lined up in front of them. An excellent keeper can feature in the same team as a dodgy defence, and vice-versa.
There isn’t really an empirical way of deciding whether a goalkeeper is better or worse than another, statistically speaking. We may not be able to definitively be able to answer the question of who the Premiership’s best goalie is – statistical data on the quality of any given save is hard to come by – but we can certainly find out which number one is the most important to their team.
By examining each Premiership goalkeeper’s expected goals against (xGA), and comparing it to their actual goals conceded, we can gain an insight into how valuable each keeper is to their team. The principle is relatively straightforward. If a goalkeeper’s xGA is lower than the number of goals conceded, then they’re probably shipping goals that could be saved by a better goalie. If their xGA is higher, then it’s fair to say they’re overperforming and preventing goals that another keeper in the same situation might not necessarily stop.
Which leads us to the above table, which shows each Premiership keeper’s goals against and xGA per 90 minutes. There are currently five Premiership goalkeepers whose xGA currently eclipses their actual goals conceded; Joe Lewis, Craig Gordon. Zdenek Zlamal, Liam Kelly and Allan McGregor. What this means is that these five players are excelling between the sticks and denying opposition goals that should really be hitting the back of the net.
The larger the surplus between a player’s xGA and their goals conceded, the greater an impact they’re having on their team. McGregor does indeed impress here – he’s conceding 0.26 fewer goals per game than he reasonably should – but by this metric, Hearts’ Zlamal is actually the clear high-performer with a gap of 0.39. In a nutshell, this means that Zlamal is more important to his team than any other Premiership goalkeeper, with McGregor close behind in second.
Zlamal’s importance to Hearts is underlined when we examine how many shots each goalkeeper has faced in the league. The Czech keeper has faced significantly more shots than any other Premiership goalie, having to contend with a total of 83 efforts on goal. For context, St Johnstone’s Zander Clark has been on the receiving end of the next highest number of shots with 75. Craig Gordon has only had to deal with 29 efforts on his goal.
Obviously, McGregor is at a disadvantage here because he plays for Rangers. Gerrard’s team tend to dominate possession and give away fewer goalscoring opportunities in defence compared to most other teams in the league. But this fact does show that Zlamal is the busiest goalkeeper in the league. So if there’s one goalie that needs to be playing well, it’s Zlamal.
What this all means is that without Zlamal in goal, Hearts would almost certainly be significantly worse off this season. As the xGA data tells us, the Hearts keeper has been performing at an excellent level so far. Due to the sheer number of shots he’s had to deal with Hearts would be leaking goals left, right and centre without Zlamal. He might not necessarily be the Premiership’s best goalkeeper, but he’s certainly the most important.