How will new-look AC Milan line up this season?

Significant investment was long overdue. The conclusion of a drawn-out takeover by Chinese investors meant AC Milan, previously handicapped on the transfer market, could spend again.

And massive changes were necessary. Although the Rossoneri qualified for this season's Europa League by way of a sixth-place Serie A finish, they did it with a subpar cast. To get back amongst the Champions League places, and to challenge Juventus at the summit, Milan had to undergo extensive surgery.

To date, CEO Marco Fassone and sporting director Massimiliano Mirabelli have drafted in seven new players at an estimated cost of around €150 million. More signings - including the potential arrival of holding midfielder Lucas Biglia from Lazio - are expected.

Manager Vincenzo Montella has already set the objective of finishing in a Champions League spot, so nothing less than fourth place will suffice.

But how will it all come together? Here's a look at the ways in which Montella can use his new team:

4-3-3

Should Montella stay true to his favourite formation, the majority of Milan's newest arrivals could fit easily into a 4-3-3 schematic.

Ricardo Rodriguez and Andrea Conti would cover the left-back and right-back positions, respectively, and Alessio Romagnoli would form a new centre-back partnership with Mateo Musacchio. Surprisingly, Musacchio is the oldest of this backline at just 26 years old.

A reliable defender with tremendous experience in La Liga, Musacchio should give Romagnoli the confidence to play the ball out from the back and push up when necessary.

Montella would have also have a trio of midfielders to carry out three different roles. Franck Kessie's athleticism would provide a crucial box-to-box presence, Riccardo Montolivo, or Biglia, would recycle possession and maintain shape, and Hakan Calhanoglu would distribute the ball and link up with the attack.

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The front three would all complement each other. With Giacomo Bonaventura and Suso capable of cutting in from either wing, promising Portuguese poacher Andre Silva should have the service to convert plenty of penalty-box chances. But Silva can also create for himself, lending more mobile qualities to an already quick attack.

4-2-3-1

Without a pair of strong midfield pivots, this formation is difficult to use. To execute the 4-2-3-1, a manager needs two defensively sound footballers who can cover lots of ground. Montella already has Kessie to fill one vacancy, and Manuel Locatelli has the attributes to play as his tough-tackling partner.

If Fassone and Mirabelli can deliver Biglia as Milan's eighth summer signing, however, this blueprint would work without a hitch. Calm in possession and efficient with the ball, the 31-year-old offers more security than the precocious Locatelli, as well as the peace of mind to allow the more attack-minded Kessie to bomb forward.

The 4-2-3-1 also needs a trequartista, and Calhanoglu can fulfill that description, having played some of his best football at Bayer Leverkusen and Hamburg as a No. 10. Given he is inclined to push forward and do damage on the edge of the penalty area, Calhanoglu would have the freedom to create chances without worrying about tracking back.

3-4-2-1

The back-three is the latest tactical trend in European football, and not necessarily because of the three centre-backs. The value of this formation is in its width, as the full-backs suddenly become more attacking and involved in the overall build-up play.

Chelsea's success last season came after manager Antonio Conte switched to the 3-4-3, and later the 3-4-2-1. It brought out the best in Marcos Alonso and Victor Moses, with the two of them overlapping Eden Hazard and Pedro.

In other words, it provided more connections, more routes to the final third, and more ways to keep the ball.

In Milan's case, Montella could rely on Rodriguez's tremendous crossing accuracy and Conti's scoring ability to create a dynamic, high-pressing system that suffocates opponents and pins them back. Calhanoglu would act like Hazard, moving into open channels and taking on defenders, while Suso would drift in from the right.

4-3-1-2

A shift back to the 4-3-1-2 - which Carlo Ancelotti used at Milan to accommodate the likes of Rui Costa, Kaka, and Clarence Seedorf - could work if Fassone and Mirabelli find another top striker to partner with Silva.

The Portuguese's background as an attacking midfielder, coupled with a tendency to drop deep, would facilitate a nice two-way relationship with a more direct goal-scorer like Pierre-Emerick Aubameyang, Andrea Belotti, or Nikola Kalinic - all of whom have been linked with the San Siro outfit.

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Fabio Borini, who arrived on an initial loan deal from Sunderland, could technically play alongside Silva, but it wouldn't make sense to shift formations to accommodate an admittedly profligate striker.

And there aren't many two-striker systems which also make space for a creative midfielder like Calhanoglu. This one does. Bonaventura would apply his industriousness to a left-midfield role.

However, there are drawbacks. A narrow setup by default, it would put a lot of pressure on Rodriguez and Conti to get up and down the pitch, and if the midfielders were to move out wide, the middle of the park would be susceptible to a well-timed counter-attack.