The summer transfer window is set to close on 31st August and it looks like there still can be some record-breaking signings with Real Madrid eyeing 18-year old sensation Kylien Mbappe and Neymar considering a huge move from FC Barcelona to Paris Saint-Germain that has forced UEFA to flag the move as it might breach the Finacial Fair Play clause. The other rumours that are doing rounds are Gareth Bale's speculated move to Manchester United while it is being reported that Phillipe Coutinho has almost struck a deal with Spanish giants FC Barcelona and it is just a matter of time before the Liverpool star will announce his move to La Liga. 

Here is a look at the biggest transfers that could make a huge difference in the upcoming football season:

The Belgian international made his English Premier League debut with Chelsea but was mostly a part-time player for the Blues. The 24-year old moved to Everton in the 2013-14 season and started his career with the Toffees with a bang scoring a winning goal against West Ham United on his debut. The Belgian did not look back from there on and helped Belgium reach the quarterfinals of the 2014 FIFA World Cup scoring against the USA in the round of 16. Lukaku picked up from where he left in the EPL scoring 20 goals in 47 games for Everton in the 2014/15 campaign followed by 25 goals in 46 matches in all competitions in 2015/16. Lukaku came out even stronger in the 2016/17 campaign scoring 32 goals in 43 appearances for club and country becoming Everton's all-time top scorer and one of the most sought-after player in all the leagues over the world. With Wayne Rooney heading out of Old Trafford, Lukaku will bring in the much-needed sting in the Red Devils alongside Paul Pogba.

2. Alvaro Morata (£60 million) to Chelsea from Real Madrid:

3. Benjamin Mendy (£52 million) to Manchester City from AS Monaco:

The Paris born made 100 appearances for Marseille before being roped in by AS Monaco for £11 million. The 23-year old left-back helped the club to win their first Ligue 1 title since 2000 and also helped the team reach the semi-finals of the UEFA Champions League. After missing out on Dani Alves who changed his mind at the last moment and decided to move to PSG after committing to sign with Manchester City Pep Guardiola did not want to miss out on Mendy and paid a record £52 million to acquire the French international's services breaking the world record for signing the world's costliest defender in Kyle Walker who was roped in by Manchester City itself.

The English right back debuted with the Tottenham Hotspur in 2010 but became a regular first-choice defender only after he completed his loan stints with Aston Villa and Queens Park Rangers. Walker scored the winning goal against Arsenal in the North London derby shooting brilliantly from 25 yards out of the box to fetch Spurs a 2-1 win. The 27-year old was the part of the PFA(Professional Footballers' Association) Team of the year alongside the likes of Gareth Bale and won the PFA young player of the year award in 2012. Walker continued to spearhead Spurs defense in the following seasons and made the right-back position his very own. However, Walker could not resist himself from joining Manchester City owing to the presence of Pep Guardiola as the manager of the team which made him the costliest English player ever in the history of the game.  

5. Nemanja Matic (£40 million) to Manchester United from Chelsea:

Manchester City also signed Bernando Silva from Monaco while Leonardo Bonucci's move from Juventus to AC Milan shocked Italy. Liverpool acquired the services of forward Mohamed Salah while Alexander Lacazatte was bagged by Arsenal for £46.5 million.