Roma failed to take advantage of a 10-man Lazio, drawing 1-1 in the Derby della Capitale.
The Giallorossi are still emerging from the shadows of a Zdenek Zeman reign that was plagued with inconsistency and controversy, and it was surprising to see Aurelio Andreazzoli opt for a different formation in such a crucial game.
Check in for the top tactical takeaways from one of Italy's premier games.
Under Aurelio Andreazzoli, Roma are a fascinating watch.
The interim coach has experimented in wild ways to get his team clicking, and his record so far would suggest that he's been largely successful in unlocking the offensive talents at the capital club.
But defensively, they still lack organisation and presence, a veritable hangover from the Zeman era.
When using the three-man defence, Roma had enough bodies back in the right areas to release wing-backs and midfielders with ease. Switching to the 4-4-2 diamond against Lazio, they were caught out on numerous occasions.
Marquinho is no left-back, but his vertical movement makes him an ideal left-wing-back. Antonio Candreva isolated him easily, and the Brazilian was often sucked in, leaving gaping holes down the flank.
Alessandro Florenzi was a little too wasteful to be paired with Marquinho. Lazio did a lot of damage on the flanks and on the breaks due to positional indiscipline.
As suspect as Marquinho was defensively, Marquinhos was superb.
He gave away a penalty through naive use of the arm, but the 18-year-old is going to make some mistakes considering his genuine lack of experience.
He has made absolutely massive strides in his first full season of football, becoming the undroppable centre-back in the capital.
His positional sense is wonderful, beating most players and clearing most balls with his anticipation and first few steps alone.
One of the main issues with Zeman's Roma was the defensive irregularities.
The Czech all but sacrificed the art of defending despite possessing talents such as Alessio Romagnoli and Marquinhos, leading to mass indiscipline when tracking back.
Andreazzoli has fixed some of the issues, but organised pressing remains a difficult concept to grasp.
Lazio maintained an element of control for long periods of the game, as Roma continually played direct into Erik Lamela and Francesco Totti, and the Giallorossi's attempts to press and harry were disjointed.
They struggle to do it as a unit—particularly on the left—and leave holes for their opponents to utilise.
A lot is made of Roma's high-profile young stars.
Marquinhos, Lamela and Miralem Pjanic steal the headlines, but Florenzi deserves to be in the conversation, too.
He's still experiencing growing pains at the age of 22, but that's due to lack of stability in the managerial capacity at the Olimpico. When he finally gets settled, he'll progress quickly in a familiar role.
He's been asked to fulfill a vast number of positions under his many head coaches, but box-to-box midfielder looks the most promising for him.
He has the guile, the quickness and the awareness to succeed in a rapid attack and thrives when given pace to run into.
The loose role that he's enjoyed in both the 4-3-1-2 and the 3-5-2 has suited his game down to the ground.