That's why Flashscore.com, in cooperation with a team of analysts from Czech data company 11Hacks, is bringing you a data-driven overview every Friday of where those (un)expected results might occur in the wide world of football.
AC Milan vs Torino
AC Milan haven't won a league match in five attempts. They have only managed to pick up a single point in important clashes against Roma, Lazio and Inter, and have failed to win against Lecce and Sassuolo during that period. Adding to that, the 14 goals conceded in that stretch were not the result of chance but due to a large number of chances conceded in dangerous areas.
At the beginning of January, according to mathematical models, Milan had the second-best defence in Serie A, which in terms of the quality of shots conceded was somewhere around the level of Naples and Inter. Only Roma conceded fewer dangerous chances against their opponents.
This is a good example of how injuries to key players have a huge impact on a team's play and the poor performance of the goalkeeper. In the case of Milan, these are connected issues.
In the last three games, key centre back Fikayo Tomori (25) has been plagued by health problems and defensive midfielder Ismael Bennacer (25) has also missed the last two outings. With an important Champions League tie against Tottenham coming up, the next league game may not see either of them start once again.
A long-term problem for Milan is the absence of their goalkeeper Mike Maignan (27), one of the key players in their title-winning season. While in Maignan, Milan had the best goalkeeper in Serie A, in his understudy - Ciprian Tatarusan (37) - they have the worst.
According to mathematical models, the Romanian goalkeeper has conceded five more goals than he should have considering the quality of the opponent's shots. In terms of minutes played, no other Serie A goalkeeper is doing as badly.
In the match between the league's sixth and seventh teams on Friday evening, Milan face Torino at home.
Torino manager Ivan Juric's (47) side are right on the league average in terms of the quality of chances created and have the sixth-best defence in the league. On top of that in their favour is the impressive form of their goalkeeper Vanja Milinkovic-Savic (25).
Moreover, Torino manage to create dangerous chances from set-pieces, from which Milan have already conceded nine goals - the same number as last-placed Cremonese. The biggest threat to Milan's defence in this respect is stopper Alessandro Buongiorno (23), who is getting chances regularly.
Liverpool vs Everton
Liverpool's current 10th place in the Premier League table is the culmination of a long run of factors. These include fatigue and injuries to key players, the absence of reinforcements in the midfield, failed tactical changes, defensive errors and, to a large extent, bad luck.
All of this has had by far the biggest impact on the team's defensive performance which is the fifth worst in the Premier League in terms of the quality of chances conceded - roughly on par with Bournemouth, Leicester and Crystal Palace.
While Arsenal and Manchester City are conceding an average of 0.8 expected goals per game, Liverpool are currently at a whopping 1.50.
The situation has been even worse since the December commencement of the competition - e.g in the last six games played. In this period, no other team has allowed their opponents to have more major chances.
In such small samples of matches, the difficulty of the draw does come into play but it has been relatively kind to the Reds as they faced Aston Villa, Leicester and Brentford in succession, then Brighton, Chelsea and most recently Wolverhampton.
According to the mathematical models, they should have conceded 10 times in this period, which even with Alisson (30) in goal is a concern. In reality, they conceded nine goals.
Despite those problems, at the other end of the pitch, Liverpool have had no such trouble and create chances with a similar frequency to Manchester City, the team with the best attack in the Premier League. However, their attacking players are enduring a period where they are burning one big chance after another.
Mohamed Salah (30) and Darwin Nunez (23) have combined to score only once since December, yet they have already had 25 shots on target from inside the box. Based on the quality of those shooting opportunities, they should have had five goals.
Everton are admittedly one of the most defensively vulnerable Premier League sides but with new coach Sean Dyche (51) in charge for their last game they kept Arsenal a respectable distance from their own goal. Fortunately for them, in Jordan Pickford (28), they have one of the best goalkeepers of the season.
In addition, Everton are a threat from set pieces - thanks to the presence of James Tarkowski (30), Amadou Onana (21) and Dominic Calvert-Lewin (25).
Liverpool are, at best, mediocre defensively and will probably still be without the injured Virgil van Dijk (31). For all these reasons, this is a match in which anything could happen.
Legia vs Cracovia
This is a contest between two evenly-matched teams in Poland's Ekstraklasa with a lot to play for. Cracovia, currently ranked sixth, should be fifth according to the mathematical metric of expected points, which is mainly due to their very good defensive performances.
In terms of the quality of shots conceded, they are the fourth-best in the whole league. The team defends the central spaces of their own backline very well and goalkeeper Karol Niemczycki (23) has also contributed significantly to the team's solid defensive displays.
He is one of the best goalkeepers in the league right now and in terms of data he is performing similarly to Vladan Kovacevic (24) from league leaders Rakow. Cracovia have only conceded nine goals so far in open play and just 14 including penalties.
In terms of defence, Legia is similar. However, their young goalkeeper Tobiasz Kacper (20) is not yet up to Niemczycki's quality. In terms of the number and quality of chances created, both teams have almost the same numbers, and the same goes for taking and defending set pieces.
With such evenly matched data, this is another match from the weekend's football action in which the underdog could spring a surprise. Follow all the matches on Flashscore.com to see if the favourites fall.
