Jan Oblak
Jan Oblak has become a crucial player for Diego Simeone Getty

Jan Oblak has committed his long-term future to Atletico Madrid, signing a deal that lasts until 2021 following speculation linking him with a summer move to Manchester United. Spanish newspaper AS said Diego Simeone had "sent a message" to the Premier League outfit by increasing the player's release clause to €100m (£77.5m, $112.6m) as part of a new contract that makes it clear the goalkeeper is not for sale.

Atletico Madrid have been forced to cash in on a numbers of key figures such as Diego Costa, Sergio Aguero, Radamel Falcao and Arda Turan in recent seasons due to the club's financial situation. However, following the impressive 2014-2015 campaign – where they won La Liga title and reached the Champions League final – the club are trying to change that policy and keep themselves in the title battles with Barcelona and Real Madrid.

Atletico Madrid have increased Oblak's clause to €100m. AS

AS claimed Los Colchoneros rejected the Premier League giants' intentions to lure the custodian last summer. Louis van Gaal's side were, at the time, looking to bolster that position ahead of the expected departure of David de Gea to Real Madrid – which later collapsed on deadline day due to a paperwork issue.

With reports in Spain suggesting Real Madrid could make a new approach for De Gea in the summer, Atletico have pre-empted any further Old Trafford interest by tying Oblak to the club until 2021.

"Jan Oblak and our club have reached an agreement for the extension of the Slovenian goalkeeper's contract until 2021. The current Zamora [top goalkeeper] of the BBVA League has signed his new contract at the Vicente Calderón stadium, extending our relationship for another season," the club confirmed through an official statement.

Simeone's side refused to disclose further details on the new contract but AS claims it includes an increase in the release clause from €50m to €100m to "send a message" to suitors that Oblak's exit from the Calderon is impossible.

Oblak, who has conceded just 11 goals in 23 games this season, has expressed his delight over the agreement, adding that he wants to stay at the club for the long-term.

"It shows the club trust me and I'm very happy about that and grateful to everyone who has helped me renew my deal," he said. "I feel very good, to be honest. I'm very happy here, with the whole team, the technical staff and all the people working here. So I renewed because I want to continue here."