VIRGIL VAN DIJK - Southampton to Liverpool, £75m
Liverpool were fended off Van Dijk in June 2017 after being accused of tapping him up by Southampton, but the defender's absence from several matchday squads thereafter meant a departure was never far away.
The Reds gave their fans a late Christmas gift in December of the same year, confirming the Netherlands international's arrival and he has looked worth every penny since making the switch to Anfield.
LUCAS HERNANDEZ - Atletico Madrid to Bayern Munich, £68m
Having featured as France's first-choice left-back in their triumphant 2018 World Cup campaign, it did not take long for other clubs to begin being linked with Lucas.
Bayern were reported to have things tied up with the defender by the end of the year, though it was said they were trying to avoid paying his full release clause.
As it happened, Atletico received the €80m required to trigger Lucas' exit at the end of the season, meaning Bayern have secured themselves a player who could cover two positions at the very top of the sport for the next decade.
BENJAMIN MENDY - Monaco to Manchester City, £51.75m
Pep Guardiola broke the record for a defender when he signed Mendy from Monaco in July 2017, the left-back having quickly established himself as one of Europe's most exciting attacking full-backs as his side won the 2016-17 Ligue 1 title and reached that season's Champions League semi-finals.
His arrival was part of a spectacular overhaul of the City backline, which saw them spend close to £165m on three defenders and goalkeeper Ederson, but two serious knee injuries curtailed what looked to be a promising start to life in England.
DAVID LUIZ - Chelsea to Paris Saint-Germain, £50m
Paris Saint-Germain paid a whopping fee to sign Brazil international David Luiz from Chelsea in 2014.
He won Ligue 1 in both of his seasons at PSG and made it three top-flight titles in a row after he surprisingly returned to Chelsea for £34m in August 2016, claiming his first Premier League winners' medal.
KYLE WALKER - Tottenham to Manchester City, £50m
When Walker joined Spurs from hometown club Sheffield United for £5m in 2009, few would have guessed he would one day become the most expensive English player ever.
He quickly established himself as a key component at the back following his July 2017 arrival and has won two EFL Cup titles and the Premier League. The Champions League and FA Cup could yet be added to that list this season.
JOHN STONES - Everton to Manchester City, £47.5m
City have certainly shown a willingness to pay large amounts for English talent, with Stones having joined the club from Everton in 2016.
The 24-year-old had a difficult first campaign as Guardiola's side under-performed, but his displays have since improved considerably, despite a few injuries.
EDER MILITAO - Porto to Real Madrid, £42m
Another transfer set to go through at the end of the season, Madrid caught many by surprise when it was announced earlier in March they had paid the release clause of Porto's Brazil international Militao. The 21-year-old was only brought to Europe from Sao Paulo in 2018 and appears to represent something of a gamble by Los Blancos.
DAVINSON SANCHEZ - Ajax to Tottenham, £36.6m
Spurs waited several weeks to make their first signing of the close-season transfer window in 2017, but they did so in some style, smashing their club record to bring Sanchez to north London.
The former Atletico Nacional man reportedly caught Barcelona's attention during Ajax's run to the Europa League final in 2016-17 and has looked a solid addition to the Premier League since arriving.
LEONARDO BONUCCI - Juventus to AC Milan, £35.2m
A row with Juve head coach Massimiliano Allegri led to Bonucci being allowed to join Serie A rivals AC Milan in 2017, who splashed the cash in a bid to return to the Champions League.
Bonucci won six Serie A titles at Juventus but such success did not follow at San Siro. His form suffered until he secured a return to Turin just a year later.
SHKODRAN MUSTAFI - Valencia to Arsenal, £35m
Arsenal are not normally known for their big spending, with former boss Arsene Wenger one of world football's more parsimonious managers, but they forked out £35m to sign Mustafi from Valencia in August 2016.
The Germany international had a solid first campaign at Emirates Stadium, but the Gunners missed out on Champions League qualification for the first time in 20 years in 2016-17. He seems to have regressed since, often receiving criticism from supporters.