Paris Saint-Germain (PSG) perhaps made a big mistake by signing Sergio Ramos in the summer. The French club are already out of the Champions League and Coupe de France. While they are primed to win the Ligue 1 title, they were recently beaten 3-0 by AS Monaco. So things in the French capital are certainly not hunky Dory and the former Real Madrid captain has come under scrutiny of late.PSG made a blunder by signing Sergio Ramos in the summerTransfer News Live@DeadlineDayLive Sergio Ramos is considering leaving PSG, just one year after joining the club from Real Madrid. (Source: @AndiOnrubia)10:26 AM · Mar 14, 20222190215🚨 Sergio Ramos is considering leaving PSG, just one year after joining the club from Real Madrid. (Source: @AndiOnrubia) https://t.co/UQHWzmRw4gAlthough the soon-to-be 36-year-old defender was one of the best centre-backs a couple of years ago, that is not the case anymore. The Spaniard has lost a lot of pace and is far more injury prone now. This has led to him making only five appearances across all competitions and none of them have come in the UCL. The Ligue 1 club might now look back on this deal with great regret. This is especially since they could have signed someone who would have boosted their chances of winning European silverware instead of Ramos.On that note, let's take a look at five players PSG could have signed last summer instead of sealing a move for Ramos.#5 Dayot UpamecanoFC Bayern München v SpVgg Greuther Fürth - BundesligaDayot Upamecano has been one of the best defenders in the Bundesliga over the last couple of years. The centre-back was one of the main players under Julian Nagelsmann at RB Leipzig and followed his manager to Bayern Munich last summer.101 Great Goals@101greatgoals RB Leipzig centre back Dayot Upamecano has decided to join Bayern Munich in the summer, according to L’Equipe and RMC. What a signing!12:25 PM · Feb 13, 202129132🔁 RB Leipzig centre back Dayot Upamecano has decided to join Bayern Munich in the summer, according to L’Equipe and RMC. What a signing! https://t.co/zZp832n0H0However, his performances at Leipzig were enough to convince the best in the business to secure his services. An absolute behemoth at the back, Upamecano can strike fear in the eyes of most opponents through his massive stature and strength on the ball and in the air. He is also an excellent passer of the ball, evident with his four assists in 22 Bundesliga appearances this season.Ramos certainly has a lot more experience than Upamecano. But the Frenchman was arguably a better fit for PSG, given their high pressing tactics and dynamic play.#4 Ibrahima KonateFC Internazionale v Liverpool FC: Round Of Sixteen Leg One - UEFA Champions LeagueIbrahima Konate is yet another RB Leipzig product who found a new destination last summer. But unlike his former centre-back partner Upamecano, the 22-year-old ace decided to move to England to join Liverpool.Anything Liverpool@AnythingLFC_Ibrahima Konaté's record for Liverpool across all competitions:WWWDWWWWDDDWWWWDWWWUnbeaten 4:58 AM · Mar 21, 20226281251Ibrahima Konaté's record for Liverpool across all competitions:WWWDWWWWDDDWWWWDWWWUnbeaten 😤 https://t.co/9yqihvNa9WA fast, agile and tactically astute defender, Konate has certainly been a hit at Anfield. While he may not be the first name on the team sheet, he has been integral to the side in the cup competitions. However, given his age (22) and raring potential, he is sure to become the starting centre-back at Liverpool in the coming years. PSG could have decided to sign the French international and partnered him at the back alongside Marquinhos and Presnel Kimpembe.Ramos' trophy collection was enough to suggest that he could have been a good signing. However, Konate would have been the better bet, especially in the long scheme of things.#3 Cristian RomeroBurnley v Tottenham Hotspur - Premier LeagueCristian Romero was the standout centre-back in Serie A for Atalanta last season, as evidenced by his Serie A best defender award. Understandably, several clubs were interested in signing him in the summer, but PSG were not one of them.Jules Tottenham Bevis 🖊@julesbevisCristian Romero is fast becoming one of the best centre backs in the Premier League, Pace, Aggression, Cool on the ball, Gets in his opponents head. Got a nasty streak which I like 2:38 AM · Mar 21, 20228Cristian Romero is fast becoming one of the best centre backs in the Premier League, Pace, Aggression, Cool on the ball, Gets in his opponents head. Got a nasty streak which I like 😏 https://t.co/aX5wWuy5wnTottenham Hotspur ended up signing the Argentinian star and he has since been one of the best defenders at the club. Although he was unavailable for a couple of months due to injury, Romero has shown some classy moments in the famous white jersey. His calm nature on the ball and ability to act as a threat in offensive set pieces has been a real blessing for manager Antonio Conte. These are the qualities one also associates with Ramos, but the South American star is 12 years younger than the four-time Champions League winner.So while PSG did opt for a more experienced player, signing Romero would have boded far better for them, given his performances in recent seasons.#2 Raphael VaraneManchester United v Tottenham Hotspur - Premier LeagueRaphael Varane spent nearly a decade playing alongside Ramos at Real Madrid as the duo picked up silverware year-after-year. But the two decided to exit Santiago Bernabeu last summer and while the Spaniard joined PSG, the Frenchman joined Manchester United.bet365@bet365He's been hailed as one of the best defenders in world football.A stalwart at the heart of Real Madrid for a decade, he played over 300 times, lifting every major club honour available.His new challenge awaits at the Theatre of Dreams.Raphaël Varane joins Manchester United.11:30 AM · Jul 27, 2021115He's been hailed as one of the best defenders in world football.A stalwart at the heart of Real Madrid for a decade, he played over 300 times, lifting every major club honour available.His new challenge awaits at the Theatre of Dreams.Raphaël Varane joins Manchester United. https://t.co/pDBOW4OyN0Although Varane has not exactly been a hit at Old Trafford, he has arguably been one of the better players at the club this season. Moreover, he has struggled with injuries and the change in managers has not helped him settle down well either. Regardless, he is a defensively resolute player and would have arguably been a far better investment than Ramos. Still only 28, PSG could have churned the best out of Varane's peak years had they decided to sign him instead of Ramos last summer.#1 David AlabaReal Madrid v Paris Saint-Germain: Round Of Sixteen Leg Two - UEFA Champions LeagueDavid Alaba was one of the key perpetrators who helped Real Madrid edge past PSG in the UCL Round of 16 tie this season. The defender left Bayern Munich in the summer and joined the 13-time European champions on a free transfer.Transfer News Live@DeadlineDayLivePSG and Liverpool both made an offer to sign David Alaba but the defender chose Real Madrid, where he has always dreamed of playing. (Source: @FabrizioRomano)1:59 AM · Jan 19, 20211372147PSG and Liverpool both made an offer to sign David Alaba but the defender chose Real Madrid, where he has always dreamed of playing. (Source: @FabrizioRomano) https://t.co/18o5x3uM4iOne of the best in the business, Alaba has been at the top of European football for over a decade now. The left-back turned centre-back has the tactical nous and defensive solidity that most teams would want in their defenders. Moreover, he has years of experience in winning trophies and still has a lot left in the tank. PSG rarely shy away from paying the big bucks. Hence, they could have jumped the gun to seal a move for Alaba last summer instead of signing Ramos.The Austrian star is six years younger than the 2010 World Cup winner and could have helped PSG in the knockout stages of the UCL this season. However, the Ligue 1 giants will now have to find a way to get their veteran star back to his best.