The Premier League never saw Sebastien Haller at his best — but West Ham’s loss is proving to be Ajax’s gain.

Haller became the Irons’ record signing when he joined David Moyes’ side in July 2019, yet he failed to consistently deliver at the London Stadium.

The Ivory Coast international was sold to Ajax 18 months later and has not looked back, firing the Amsterdam-based club to the top of the Eredivisie table.

With de Godenzonen back in domestic action against Heerenveen this weekend, here is why the Paris-born forward is scaling new heights at the Johan Cruyff Arena.

West Ham woes

Expectations were high when the Hammers signed Haller for a club-record fee of £45million — but West Ham supporters should perhaps have known better.

Club owners David Gold and David Sullivan had recruited over 40 forwards before Haller's arrival, with few of those additions proving to be a success.

True to type, the former Auxerre frontman managed just 10 goals in 48 league appearances, with the Irons quickly cutting their losses and selling the forward to Ajax for £20m.

And on his arrival in the Dutch capital, Haller aimed a subtle dig at his former club.

He said: "I knew that I would be trusted [at Ajax] and that I would have the opportunity to play the leading roles to win titles."

Europa League embarrassment

Haller’s life in Amsterdam did not get off to the best of starts, with the 6ft 3in attacker being left out of Ajax’s Europa League squad.

De Godenzonen were left with egg on their face after it was revealed that they had mistakenly left the club’s record signing off their European registration list.

UEFA rejected Ajax’s appeal to allow Haller to compete in continental competition, with significant consequences for the Dutch champions — Erik ten Hag’s men crashed out in the quarter-finals of the competition to Roma as they struggled to muster the firepower to overcome a first-leg defeat.

Dutch dominance

Despite that mishap off the pitch, Haller took to life in the Eredivisie like a duck to water.

After toiling in front of goal for West Ham, he found his shooting boots — racking up 11 league strikes in just 19 appearances and providing five assists.

He has started the current campaign in a similarly rich vein of form too, netting five times and setting up his team-mates on a further two occasions.

The six-cap international currently sits joint-second in the race for the Eredivisie top scorer but with Ajax notching 30 goals in their first eight fixtures, Haller is certainly in the right place to ultimately claim that crown.

Frankfurt form

Haller has clearly rediscovered the form he displayed at Eintracht Frankfurt, which prompted West Ham to break the bank and bring him to East London.

The forward was part of a remarkably potent front three, consisting of Haller, Luka Jovic and Ante Rebic.

The trio scored 41 Bundesliga goals between them in 2018-19 and also led Die Adler to the Europa League semi-finals.

If Ajax’s No22 maintains his current levels then he will surpass the 15 goals he scored that year and should top his best-ever league tally, for Utrecht in 2015-16.

Champions League exploits

Haller has also displayed his prolific nature on Europe’s biggest stage, as he currently tops the Champions League goalscoring charts.

The 27-year-old has hit the ground running, with five goals in his first two games in the competition.

In fact, Haller scored four times in his first ever Champions League tie — a 5-1 demolition of Sporting in Lisbon.

With such an impressive start to life at the continent’s top table, Ajax and their talismanic targetman could certainly be set to surprise some of the game’s elite clubs over the coming months.