Agent: United's shown most 'concrete interest' in Griezmann

Of all the teams to inquire about possibly signing Antoine Griezmann, Manchester United has demonstrated the most interest in the Atletico Madrid star, according to the French forward's agent, Eric Olhats.

Because Griezmann's contract with Atletico Madrid includes an £85-million (€100-million) release clause, Olhats said the 25-year-old's suitors have been limited to Europe's top clubs.

"We’re at the stage of gathering information from clubs who have a concrete interest," Olhats told French television show "Telefoot," as translated by Reuters.

"There is an unavoidable €100-million clause so that restricts the number of candidates. You have United, (Manchester) City, Chelsea, Barcelona and Real Madrid. United were the first to come and see us and the most concrete in their wishes."

Olhats' comments add substance to reports that United intends to activate that clause in Griezmann's contract after identifying him as its top target entering the summer.

Griezmann, however, hasn't revealed any serious interest in joining another club since insisting in March that there's "no reason" to leave Atletico.

The Red Devils have had Griezmann in their sights throughout the season as they attempt to upgrade their attacking core.

The team's crop of forwards has even been criticised by manager Jose Mourinho. His side enters the final weeks in a perilous position without top scorer Zlatan Ibrahimovic, who was ruled out for the remainder of the campaign after suffering knee ligament damage.

Outside of Ibrahimovic's 17 Premier League goals, Juan Mata and Marcus Rashford are the next top scorers with six and five goals, respectively.