Manchester United's interim head coach Ruud van Nistelrooy has admitted he has "mixed emotions" ahead of his first game in charge of the club after the sacking of Erik ten Hag.

Van Nistelrooy, a club legend who scored 150 goals in five seasons under Sir Alex Ferguson during his playing career, will take the reins for the first tome on Wednesday as United host Leicester City in the Carabao Cup round of 16.

"As I am sure everyone can imagine, I am writing these notes with a huge amount of mixed emotions," Van Nistelrooy said in the programme for the cup fixture.

"Erik ten Hag brought me back to Manchester United in the summer and, while I have only been part of the coaching staff here for a few months, I will always be grateful to him for giving me the opportunity, and I am saddened to see him leave.

"Even on an interim basis, it is a great honour to manage the club I love for however long I am asked to do so. I can promise that I will continue to give my all, in whatever capacity, to try to turn around our fortunes.

"Despite our results, I am loving being back at Old Trafford and working with the team and staff every day. We've seen the squad's potential at times this season, but clearly not often enough."

Van Nistelrooy added that he feels United can return to the upper echelons of world football and called for the fans to back his team as a new era begins.

"Now is the time for everyone at the club to work together, give everything and turn this season around while we have time. From my experiences as both a player and a coach here, I can say for sure that when players, staff and supporters pull together, Manchester United can be unstoppable," he said.

How long the Dutch coach will remain in charge is as yet unknown, as United are engaged in talks with Sporting CP over their head coach Rúben Amorim.

The deal moved closer earlier on Tuesday with the Portuguese club informing the country's financial regulator that United had confirmed their willingness to pay Amorim's 10 million ($10.79m) release clause.

Sources have told ESPN that United are determined to seal a deal for the highly rated coach to replace Erik ten Hag before Sunday's Premier League clash against Chelsea.

United are aware of other complicating issues such as a mandatory notice period, sources told ESPN, but remain confident an agreement can be reached.

Information from ESPN's Mark Ogden contributed to this report.