Football is a mistake-ridden game, so much so that the majority of goals can be brought back to a mistake. So while mistakes are inevitable, some cannot be ignored and during matchday 21, there were plenty on offer.

Bayern Munich won 8-0 against Hamburg, but hidden behind this historic result was the goal that started it all. Rafinha's cross was handled by Ronny Marcos, yet the defender had very little time to react. While his arms weren't behind his back, he wasn't moving towards the ball.

Big calls in Munich are perhaps not the same as elsewhere. After that, Hamburg collapsed. Yes, the bold 4-4-2 formation, the early injury to Ivica Olic and the stand-off defending all contributed to that, but the decision to award a penalty was where it started.

Every goal in Werder Bremen's 3-2 win against Augsburg came from a set-piece. That fact alone hardly bodes well if we're talking about mistakes because defending set-pieces is perhaps the easiest situation to practice in football. Admittedly, there are players like Zlatko Junuzovic who make defensive criticism difficult, but Lukimya does find himself very open, very quickly for his goal.

Ragnar Klavan embodied the hero to zero metaphor perfectly. Having scored a good header, he then lunges when he needs to stand his ground, offering Davie Selke the chance to embellish the foul.

There's risky defending - as I pointed out with Mats Hummels and Bayern recently - but this was one step beyond that. Then right-back Theodor Gebre Selassie, who is just five feet 11 inches, snuck in at the near post to head the ball in. It's like Philipp Lahm scoring a header.

It was worse in Leverkusen. Centre-back Kyriakos Papadopoulos executed a textbook equivalent of an air shot with his head and Bast Dost said thank you very much. Then goalkeeper Bernd Leno dived but forgot to make the save, before Leverkusen failed to close down two consecutive crosses and Dost delivered again.

Then the officials failed to spot a foul when Heung-Min Son kicked the ball out of the hands of Diego Benaglio. This decision caused Wolfsburg's defence to wobble and the home team and crowd seized on it. Benaglio made the mistake of rushing out of goal soon afterwards. 3-2. Dost scored as Leverkusen's defense turned into estate agents (again), before Wolfsburg were beaten by Son in predictable Arjen-Robben-style.

If Robin Knoche doesn't jump that early, Leverkusen might not have scored that fourth. In the same breath, if Papadopoulos and/or Leno decide not to shirk responsibility at the near post, then Dost doesn't score four.

When the New England Patriots looked down and out against the Seattle Seahawks in Super Bowl XLIX, Patriots head coach Bill Belichick had one simple message for his players: "Do your job."

It's a sentiment many Bundesliga defenders should consider, especially after today.