It wasn't easy for Arsenal to get past Swansea, but the Gunners eventually made their breakthrough late in the game and never looked like relapsing, as they have so many times this season.
During the first half, both teams played to a stalemate. There was not a whole lot of difference between the sides, and both came close to scoring on a few occasions. At halftime, there was a feeling that the game was bound to erupt at some point in the next 45 minutes.
Yet that reaction needed a catalyst. And there did not immediately appear to be one for either side. Alex Oxlade-Chamberlain was superb in the first half, twice hitting the woodwork with searing strikes, but he was unable to create a whole lot after the break before Arsene Wenger hauled him off in the 71st minute.
Theo Walcott was having one of "those days," when he vaguely threatens to shred an opposition's defense but never actually comes close to doing so. Mikel Arteta was stuck in his position at the back of Arsenal's midfield, and apparently no one told Olivier Giroud that a football game was going on.
Abou Diaby also seemed to forget to set his alarm before the game.
So that left Santi Cazorla.
This was not the first time this season the diminutive Spaniard has been asked to pick up the slack for his teammates. And it's an easy thing for his teammates to do: When a manager starts a player with Cazorla's obvious quality and ingenuity, he is basically inviting the rest of the team to pass the ball to him.
The Spaniard has excelled this season when put in such a position of responsibility by his teammates. One quality strike earned Arsenal a victory against Sunderland in February, and he singlehandedly drove the Gunners to victory against Reading with a hat-trick in December.
It was little surprise, then, that when Arsenal needed him most in their desperate scrap to finish in the top four, Cazorla delivered.
He was as big a part of Arsenal's domination of the game in the second half as any other member of the team, as this graphic shows (h/t FourFourTwo via Adam Hirshfield).
Clearly, Cazorla's passing was exceptionally accurate, as shown by the slew of blue arrows all over the pitch. And he was not afraid to shoot from outside the box, taking two left-footed drives from long range that Michel Vorm had to be alert to save.
And, of course, it was Cazorla's seemingly effortless, weaving run around Swansea's defense that produced the pass which Olivier Giroud bobbled into the path of Nacho Monreal for Arsenal's belated first goal.
Whenever the Gunners got forward, Cazorla was heavily involved in the attack, rotating with Alex Oxlade-Chamberlain and, later, Gervinho to keep play flowing and create chances.
A quick look at the above graphic shows that the Spaniard had almost as many passes on the left side of the pitch as he did through the center. And when he was playing as an attacking midfielder, he distributed the ball very evenly to players in all areas of the pitch.
And then there is the ability to peel off a long-range shot, which is one of Cazorla's best assets. On a different day, we would be lauding him for having the temerity to smash a long-range shot into the top corner and hailing him as Arsenal's undisputed hero for trying what no other player on the pitch would or could.
Though it was not as obvious that Cazorla was the Gunners' main maestro against Swansea, he nevertheless deserves all the plaudits he usually receives for being the best player on the day.
Without him, a top-four finish would be much less achievable for Arsenal than it is right now.