Barcelona and Sevilla have both been busy throughout the summer transfer window, despite the latter spending less than half of the former on new signings.

With the 31 August deadline still just under three weeks away, the Catalan giants’ most expensive acquisition so far is Brazilian winger Malcom, who joined from Bordeaux for £36.5 million.

Comparatively, Los Hispalenses have welcomed seven fresh faces to Seville for only £15 million more than the cost of their domestic rivals’ latest marquee player alone.

But despite the clear financial disparity between the two clubs, Sunday’s Super Cup in Tangier, Morocco is set to be an intriguing encounter.

The fixture, which will be played over one leg for the first time, represents an opportunity for Ernesto Valverde and Pablo Machin to take a look at some of their new recruits ahead of the new season.

However, this year’s instalment has become engulfed in controversy following an announcement by the Spanish football federation 24 hours before kick-off.

The governing body on Saturday ruled there would be no restrictions on non-EU players participating in the Super Cup - a match it went on to class as “not professional”.

Per the La Liga rulebook, which was thought to be applied to Sunday’s game, clubs are only allowed to name three non-EU players in their matchday squad.

The unexpected ruling means Barcelona’s decision to bring three of their four summer signings - all non-EU players - as well as Brazilian defender Marlon to Africa is permitted.

Shocked by the rule change, Sevilla are considering pulling out of what they can consider an important clash.

A club statement read: "Sevilla FC is surprised by the RFEF [Spanish football federation]'s statement 24 hours before the Super Cup,” per the BBC.

"It has stated that as many non-EU players as desired can be registered. In their last notice for the 18-19 season, only three were due to be permitted, without exception.

"The club's legal department is studying the matter and should FC Barcelona submit a team with more than three non-EU players, it would present possible ground for withdrawal on account an improper line-up.”

ERNESTO VALVERDE'S REACTION

Despite the alteration potentially giving his side an edge, Barca boss Valverde is also far from content.

"As for the Supercopa not being a professional competition, I do not know what to tell you," he said.

"I think that Sevilla are professionals and we are professionals. With all the trouble we have had this week with non-EU squad members, they could have warned us before.”

Certainly not an ideal start to the new campaign for Spain’s football authority.