Manchester United have begun the search for Michael Carrick's long-term replacement, with Ilkay Gundogan a prime contender to fill the role.

Manager Louis van Gaal has been hugely impressed with Carrick's contribution at Old Trafford this season.

The England international's passing range and ability to dictate the pace of a match has been a key feature for United.

Michael Carrick (left) has been instrumental in Manchester United's recent run of good form

United boss Louis van Gaal has been impressed with Carrick's contribution to the team

Van Gaal has identified Borussia Dortmund's Ilkay Gundogan as a long-term successor to Carrick

MICHAEL CARRICK VS ILKAY GUNDOGAN MICHAEL CARRICK Age: 33 Height: 6ft 2in Manchester United appearances: 379 England caps: 33 Honours: Champions League (2008), Premier League (2007, 2008, 2009, 2011, 2013), League Cup (2010), Club World Cup (2008) ILKAY GUNDOGAN Age: 24 Height: 5ft 9in Borussia Dortmund appearances: 86 Germany caps: 9 Honours: Bundesliga (2012), German Cup (2012), German Supercup (2013) Advertisement

But at the age of 33, the Dutchman knows the midfielder is in the twilight of his career, while the amount of time Carrick has been injured this season is also a worry.

United will seek to sign Carrick's successor this summer as part of another huge spending frenzy.

Dortmund's ball-playing midfielder Gundogan has been watched extensively by United.

Van Gaal has an intrinsic knowledge of the Bundesliga and believes the 24-year-old has the ability to take over from Carrick on a long-term basis.

Carrick, who recently signed a new 12-month extension, will continue to be part of Van Gaal's plans next season - but the club are planning for life without him.

The impending departure of manager Jurgen Klopp could see the excellent Dortmund squad unravel this summer.

Gundogan (right) has been watched extensively by United, who could make a move in the summer

Dortmund could listen to offers to avoid losing Gundogan on a free transfer in 2016

Jurgen Klopp's impending departure from Dortmund could see a host of players leave the club

Gundogan's existing contract expires at the end of next season and he is yet to sign a new deal.