Chelsea and Manchester United receive twin boost in pursuit of Antoine Griezmann

Chelsea and Manchester United have received two significant news in their pursuit of Antoine Griezmann. It has emerged that after the Atletico Madrid star revealed his decision to part ways with his agent, Diego Simeone has agreed to shorten his contract at the Vicente Calderon by two years, from 2020 to 2018.

Mirror recently claimed Jose Mourinho had earmarked Griezmann as his new marquee signing ahead of the 2017-2018 campaign following the summer arrival of Paul Pogba. However, The Telegraph also reported United faced stiff competition from Chelsea as Antonio Conte too wanted the France international at Stamford Bridge next season.

But the recent news about the Frenchman and his current manager could eventually give the Premier League giants renewed hope in their quest to lure him away from Atletico Madrid.

Firstly, because it will not be the first time a player changes agent before swapping clubs. Secondly, and even more importantly, Griezmann has never hidden the fact that his future at Atletico Madrid was linked to the fortunes of Simeone.

Griezmann, 25, had been contracted to prestigious Spanish agent Iñaki Ibañez since his childhood. The representative, who also has the likes of Xabi Alonso and Mikel Arteta as clients, eventually oversaw the Frenchman's move from Real Sociedad to Atletico Madrid in the summer of 2014.

However, the player has now revealed he has decided to sever ties with Ibañez, revealing his close friend Eric Olhats and his father will now manage his football career.

"From now I'm going to operate without an agent," Griezmann told L'Equipe. "But I will always have the advice of my father and also my mentor, Eric Olhats."

It is interesting to point out that Olhats recently confirmed that Griezmann had been the subject of interest from Premier League clubs and Paris Saint-Germain before he opted to sign a new deal with Atletico in June until 2021, increasing his release clause to €100m (£84.9m, $112m)

Griezmann later admitted that one of the mains reasons behind his decision to stay at Atletico was to continue his progress under mentor and manager Simeone.

"The only doubt (about my future) would be if Simeone leaves for PSG or wherever," Griezmann told Telefoot, as quoted by Sky Sports. "I called him before extending my contract and he confirmed to me that he was staying. I can learn a lot from him."

Atletico fans welcomed his decision as Diego Simeone committed his long-term future to the Vicente Calderon with a new deal until 2020.

However, the Argentine's future at the La Liga giants has come under scrutiny in recent months. Soon after the disappointing Champions League defeat to Real Madrid the manager hinted he could jump ship.

Simeone finally stayed at Atletico for the new campaign but now AS and Marca have added more fuel to the speculations after revealing that Atletico and Simeone agreed to amend the terms of his contract following the Champions League defeat. In this sense both Spanish publications claims that Los Colchoneros gave him a pay rise but also agreed to shorten the length of his contract by two years, from 2020 to 2018.

Should Simeone finally quit Atletico in the short-term it will be definitely easier for United and Chelsea to convince the Frenchman to switch to the Premier League.

However, they will still need to pay his €100m release clause in full to secure his services, especially after Atletico were recently handed a transfer ban for the next two transfer windows, meaning the Spaniard will be handicapped in signing a replacement for the Frenchman should he depart.