After a highly productive campaign, Liverpool had initially hoped to quietly move through the summer without any major alterations being made to the squad.

The word had been that the club desire a left-back and a versatile forward, with little else needed considering the current health of those already involved.

However, rumours have surfaced recently regarding Dejan Lovren and a potential move to AC Milan. The Italians have been linked with a £25m move for the Croatian defender, and although there are legitimate arguments to keep him, it arguably makes sense to sell at that price.

Lovren will turn 30 next month, and he's also one of the club's highest earners despite starting just eleven Premier League matches this season. Also, he's entering the final two years of his contract, and with all things considered, his value will largely depreciate from this point onwards.

From a business perspective, if his £25m valuation is met, it largely makes sense for the Reds to sanction a sale.

In such a scenario, though, Jurgen Klopp will be left with three centre-backs for the upcoming season - even though as many as seven trophies will be up for grabs.

A centre-back replacement would then certainly be on the agenda, so let's take a look at some realistic options that Liverpool could explore if Lovren was to depart.

William Saliba (St. Etienne)

Presently, William Saliba is relatively unknown, and that's largely due to the number of minutes he's played in senior football. The French defender is just 18-years-old, and he's only been on the scene in Ligue One since late September, but he's already been likened to a young Raphael Varane.

The centre-back has accumulated just 1656 minutes in all club competitions, but in that short period, he's demonstrated evidence that suggests he has a very high ceiling. He's already 6ft 4inches tall, he's composed with the ball at his feet, and he's strong when engaging with opposing players.

When compared with Liverpool's defenders this season, his defensive duel success is better than only Joe Gomez's, but his aerial success beats both Gomez and Lovren. The Frenchman's figures may have taken a hit as a result of the quality of his team, though, with his numbers likely to increase in Liverpool's functional system.

As a result of his promising profile, Arsenal are rumoured to be interested in his services, but given Liverpool's superior position at present, it's reasonable to suggest that the Anfield club would be able to edge out their London rivals if a bidding war materialised.

Ultimately, Saliba has already developed physically to the extent that he's able to play senior football competitively at just 18, but he also has significant room to evolve into a top centre-back. He'd be affordable at present, whilst offering a capable option when called upon, and it's likely that his value would only increase.

Timo Baumgartl (VfB Stuttgart)

An interesting option that would epitomise how Liverpool have operated in the market in recent times would be Timo Baumgartl. The German defender has been considered as a talent for a number of years now, but he hasn't been able to thrive in Stuggart's underperforming team this season.

His club have been regarded as an established Bundesliga club, but this season, they suffered relegation as a result of a play-off tie with Union Berlin. The centre-back could consequently be available at a cut-price fee, as was the case with Gini Wijnaldum, Xherdan Shaqiri and Andy Robertson.

Baumgartl's profile is similar to those, as he's still just 23, but he has the base from which to improve considerably whilst holding enough quality to contribute in the immediate future. He's 6ft 3inches tall, so he certainly fits the physicality criteria, and he's also proficient with the ball at his feet, showcasing his skills with regular diagonal passes across the field.

His underlying statistics aren't particularly ideal, but they have likely suffered as a result of his team's struggles. Overall, though, considering Liverpool appear intent on finding undervalued gems, Baumgartl may be an option in light of his age, his ceiling, and the fact that his current team will be playing in the 2. Bundesliga next season.

Dayot Upamecano (RB Leipzig)

A pricier option would be Dayot Upamecano, who's developing a reputation for being one of the most promising up-and-coming centre-backs in Europe. The Frenchman is contracted to RB Leipzig, who Liverpool have done business with recently for Naby Keita, and he may be attainable for the right price.

Upamecano is still just 20 years-old, he's 6ft 1inches tall, and he has an aggressive and proactive style of defending that would be suited to Klopp's assertive system. He's fairly quick for a central defender, and he's dynamic on the ball, with early traits that suggest that he's going to develop into a real leader.

However, it's worth noting that Upamecano has predominately played as a left-sided centre-back this season, which is a role that Virgil van Dijk has firmly claimed as his own. Liverpool may want two left-sided and two right-sided options ahead of next season, which would be practical, but if the club desire a like-for-like replacement for Lovren, Upamecano isn't strictly that.

The central defender has occasionally played on the right side, though, so the change wouldn't be too problematic for him. Ultimately, he may cost a little more than most targets, but given his skill set and his current age, he would be worth the investment.

Evan N'Dicka (Eintracht Frankfurt)

One of the rookies of the year from the Bundesliga this season may be an option - Evan N'Dicka. The defender has been rated as a potential signing of the season by Eintracht Frankfurt, having played over 3000 minutes to a high level after moving from Auxerre for just £5m last summer.

The Frenchman is still just 19-years-old, and he offers a very similar profile to Gomez, as he's somewhat of an all-rounder with aggression, pace, and a maturity beyond his years. Crucially, though, he has a versatile skill set, which may be of a real interest to Liverpool.

N'Dicka's positional heatmap based on his 2018/19 season
N'Dicka's positional heatmap based on his 2018/19 season

Similar to Upamecano, he's primarily played as a left-sided centre-back this season, but in his final match with Frankfurt, as well as in the U20 World Cup, he's been deployed as a left-back.

Relevantly, the Reds desire a left-back this summer to operate as a backup behind Robertson. N'Dicka has the profile of a player who could be signed for an affordable price, whilst being young enough to improve, as well as offering an option at both centre-back and left-back.