Aaron Ramsey has rightly received a lot of plaudits for the impact he has made since returning from injury. But the return of Mesut Ozil will have a greater impact on how Arsenal finish this season.
Ramsey's return to English Premier League action has seen six goals and two wins, with the Welsh ace scoring one and assisting two others.
But Ozil's appearance has been a greater boost to the speed, style and quality of Arsenal's overall attacking play. The club's record signing started the recent 3-0 away win over fellow FA Cup finalists Hull City.
Despite only playing an hour, the ex-Real Madrid star's impact was immense. The deceptively languid schemer played key passes in the buildup to each goal.
During his post-match press conference, manager Arsene Wenger highlighted the difference Ozil's passing made, reported via Arsenal.com: "Yes, he always has the timing of his pass, the incisiveness of passing makes you always turn quickly from defence to offence. That is of course very important."
The Germany international has made thoughtful and creative distribution a stylistic trademark. Ozil has that precious trait of superior speed of thought that is essential to the type of football Wenger preaches.
It is a brand of play based on intricate combinations between advanced triangles of quick-witted playmakers. As the best one of those whom Arsenal have, Ozil is very much the brain of this team.
But he didn't just revive the Gunners' attack via clever passing. Ozil's movement was every bit as effective and important.
While Ramsey's late breaks from deep have been desperately missed, Ozil's movement is different but no less valuable. Ramsey offers a direct thrust, the final flourish a combination of intelligent, forward-thinking passing needed to yield a goal.
By contrast, Ozil's movement is based on fluidity. That is another priceless quality in Wenger's vision of how to build and finish attacks.
Ozil increased the fluidity of Arsenal's midfield and forward lines against Hull. Because of his nomadic tendency to drift and wander, Ozil encourages rotation from others.
This was most obvious via his work with Santi Cazorla. The diminutive veteran Spaniard began the day on the right of Arsenal's attack.
Thanks to Ozil's penchant for roaming wide, particularly to that flank, Cazorla had greater license to drift into the middle, something he loves to do.
Arsenal's third goal at Hull was a beautiful example of this pattern in practice.
Ozil received the ball on the inside right, with Cazorla outside him, planted on the touchline. Following a quick exchange of passes, Ozil withdrew to the right, as Cazorla ran round the back of him into a central area.
Once there, Cazorla received a pass from Ramsey, which he quickly distributed to Lukas Podolski. The German forward shunted possession wide to left-back Nacho Monreal.
With Monreal on the left flank, Cazorla sneaked through the middle into the left side of the box. Monreal played him the ball, and the creative ace found Ramsey on the penalty spot.
The midfielder's snap shot was initially saved, but fell to Podolski, who had moved into the middle when Cazorla drifted to the left. Podolski scored his second and Arsenal's third to ice the game.
It was a superbly flowing move, typical of the Wenger-era Arsenal. It was a move made possible by rotation between three players: Ozil, Cazorla and Podolski.
That rotation was made possible by Ozil's knack for hovering in what Wenger would call "very interesting positions."
Speaking of positions, or more specifically, positioning, Ozil's is crucial to the way Arsenal counter. He has a talent for being in the ideal space to receive a quick ball from defence and target breaking runners on either side.
The second goal against Hull was a wonderful illustration of how Arsenal counter more effectively with Ozil in the ranks.
After City striker Nikica Jelavic erroneously claimed a foul after being outmuscled by Mikel Arteta, Cazorla passed the ball from deep to Ozil.
The £42.5 million man was hovering in the grey area just behind Hull's advancing midfielders and just in front of their deepest defenders.
He had the freedom of the centre circle to pick a pass. He chose to find striker Olivier Giroud, who had rotated from the middle to the right flank.
Giroud crossed for Ramsey, who had typically rampaged forward from deep. Ramsey chested the ball down for Podolski to forcefully slot into the bottom corner.
Watching Ozil's contribution to the goal was a reminder of the positions Dennis Bergkamp regularly took up during his glorious playing days.
The imperious Dutchman always occupied areas that made him the natural focal point of any counter. Ozil shares that same trait.
Of course, it hasn't all been smooth sailing for Ozil during his debut year in North London. He has received not unwarranted criticism for some limp performances, as The Telegraph writer Matt Law noted before the trip to Hull.
I have been as scathing as anybody about the need to have bought him in the first place, as well as his inconsistency, particularly in big games.
But the more I see Ozil live, the easier it is to appreciate the subtle, yet significant difference he makes to Arsenal. That is a difference that was more obviously highlighted by how this team played without him.
In the seven games Ozil spent sidelined with a hamstring issue, Arsenal's play was pedestrian. The midfield was often a static line with no rotation. On the rare occasions a player did make a run from deep, nobody connected with it.
Seeing how much Arsenal struggled to create without him makes sense of Wenger's decision to sign Ozil last summer.
It's no coincidence that his return yielded Arsenal's three best-scoring moves in nearly two months. It's no coincidence that Arsenal were sharp and efficient on the counter for the first time since Ozil combined with others to beat Everton, 4-1, in the FA Cup quarter-final.
Finishing fourth and winning the FA Cup are the top priorities left in a season cruelly undermined by a clutch of injuries.
With Ozil back in the fold, Arsenal have enough quality to achieve both.