With Fiorentina suddenly flying—9 straight unbeaten, 7 straight wins—the doom and gloom of the first two-thirds of the season has dissipated into immaculate vibes. Vincenzo Italiano has figured out a tactical setup that suits his players, tweaking his approach from last year to encourage more direct play and a greater focus on transitional moments. He’s also finally figured out his starting XI, which is a relief after he occasionally rotated 9 players between matches at the start of the year.

Indeed, there are only 3 real questions about ideal starters left in the team: Lucas Martínez Quarta vs Igor, Giacomo Bonaventura vs Antonín Barák (maybe vs Gaetano Castrovilli?), and Riccardo Saponara vs Jonathan Ikoné (maybe vs Riccardo Sottil/Josip Brekalo?). I’m going to run down each of those in the next week or two, but I’ll start with the centerbacks, partly because dfrank9001 suggested the topic as a poll and then I got very into the weeds trying to figure out which one I preferred.

The background

Neither Igor nor LMQ has covered himself in glory this year. While Nikola Milenković remains one of Serie A’s best defenders and is perennially linked to a Champions League contender, his colleagues at the back have been unsteady (although the Mountain that Kicks hasn’t been the picture of consistency himself). Or at least that’s been the general feeling among the fans.

Photo by Gabriele Maltinti/Getty Images

The actual numbers—31 goals conceded (1.14 per game) is the 5th-best mark in Serie A, and a massive improvement on last year’s 51 conceded (1.34 per game)—are really good. Italiano has clearly tweaked his defense a bit to solidify things at the back, mostly by keeping a fullback deeper at all times. While the back line definitely makes some mistakes, that’s the case with every side in the world. The fact that Fiorentina’s got the 5th-best defense in the league is one to celebrate, even though there’s a big question right in the middle of it.

Let’s meet our eligible bachelors

Martínez Quarta is an extraordinarily front-foot defender. His all-action, balls-to-the-wall style makes him one of the most charismatic players on the roster at times. He loves a huge tackle almost as much as he loves charging forward with or without the ball and hunting a goal; the man’s thirst for the net is unquenchable. His athleticism and technique mean that he can frequently get away with it. The downsides are that he’s prone to rash fouls and getting caught out of position. He’s also not the tallest, so despite having a good leap, he can be beaten in the air by bigger strikers.

Photo by Gabriele Maltinti/Getty Images

Igor’s calling card is that he’s may be the strongest player in Serie A. He loves shielding the ball and sending attackers flying, like a bear batting at mice. Despite that bulk, he’s incredibly quick on his feet, able to stick with quick wingers really well. He’s also silky on the ball, happily dribbling past multiple opponents and frequently pinging line-breaking passes forward. Despite his size, though, he’s a liability in the air, particularly when judging high balls in behind, and loses his man on crosses with alarming regularity.

The numbers

This isn’t the first time I’ve compared LMQ and Igor, but my opinions on them have changed. Rather, my opinion on Igor as changed: I think that he’s taken on a much more of a sweeper role, which is reflected in his defensive statistics declining across the board. Martínez Quarta, on the other hand, remains one of the best stoppers around, happily throwing himself into any and every available action and thus packing the box score.

I’ve created another comparison of the two, using fbref’s numbers. As a reminder, these numbers don’t mean that one player is necessarily better than the other. They reflect what’s happening on the pitch. I’d add that since so much of defending is about positioning, it’s one of the most difficult things to quantify. Put another way, these stats don’t end the conversation. They’re a a place to begin it.

I also thought that presenting these two without any wider context wasn’t very helpful, so I made this visualization comparing our guys against the average for Serie A central defenders, with LMQ and Igor highlighted so you can see how they stack up. The dataset is 82 players; I went through it and picked out the ones I consider central defenders, so there’s definitely some selection bias in there. I also only looked at guys who’ve played the equivalent of 5 league matches in the interest of avoiding any weird statistical outliers.

So what does it all mean?

Quantifying defending is difficult. If a defender tracks a striker’s run so well that a teammate doesn’t even bother trying to make the pass, or shepherds the ball out for a goal kick, or does any of the hundred little things that a good defender does, it might not show up on in the stats. Conversely, a defender who’s constantly out of position might have to make more tackles and blocks; while that looks good statistically, it can hurt the team as a whole as everyone else reacts to the problem spot and gets pulled out of position.

That said, I think the numbers back up the eyeball test here: after a terrible first month, LMQ’s been good. He’s the perfect dog-type defender, if you subscribe to Michael Cox’s theory of dog defenders and cat defenders. His remarkable athleticism lets him chase attackers high up and recover. More importantly, he’s settled down a bit; when I compared him to Igor last year, his penchant for fouling is what separated them.

Igor, on the other hand, seems to have taken a step back after his breakout last year. He sort of came out of nowhere, so opponents didn’t really know anything about him, which frequently gave him an advantage. With a full season’s worth of games for analysts to work on, though, clever opposition have a better idea on how to exploit his weaknesses. I’m not worried about him, as he’s a fantastic player and will likely react eventually. That he hasn’t immediately taken that next step doesn’t worry me either because growth, as I’ve said time and again, isn’t linear.

Finally, a player’s effectiveness isn’t fixed, but rather waxes and wanes. Some of that is just pure randomness: the ball bounces the right way, the opponent makes a mistake, a butterfly flaps its wings in Brazil. Sometimes a player is just on a heater: the touch is sharper, the legs stronger, the mind quicker. It’s a mix of mentality and fortune that we generally call form.

Are you ever going to stop hedging?

Okay, fine. Right now, I think that Martínez Quarta is the superior defender for three reasons. The first is that he’s cut down his fouling from last year, which made him too risky in a system that was already high-risk by design. The second is that Igor’s form has declined (the fouls, the struggles with high balls, the missed marks). The third is that the Argentine pairs better right now with Milenković.

And that, to me, is the most important thing here. Nihola is the best centerback on the roster, and getting the best out of him should be a priority. While he’s more than capable of playing as the stopper, harassing forwards high up the pitch, I think he’s better suited to more of a sweeper role. That, in turn, means that he needs a more proactive partner, and that’s certainly LMQ.

That proactivity, in some ways, limits him. He needs a more measured partner, while Milenković and Igor can both toggle between those briefs. What’s most important for the Viola, though, is that the squad contains 3 above-average defenders who can cover either of the roles in central defense in any combination. That’s huge for a side of Fiorentina’s stature; I can’t recall the last time there was quality, proven depth in central defense.

Photo by Claudio Villa/Getty Images

For a club that’s going to compete on multiple fronts, 3 competent central defenders (for a back 4) isn’t a luxury, though. It’s a necessity, as injuries and suspensions can knock guys out at any moment. Indeed, finding another capable option should be a priority this summer; nobody wants to see Sofyan Amrabat shoehorned into the back line again, and that’s a real risk right now.

The tl;dr is that I think Martínez Quarta and Igor are both good options to partner Milenković and offer different qualities. Given current form, I’d say that LMQ deserves the starting role, but I’m happy with either of these guys next to Big Nicky.