Manchester United has turned to the Dutchman Erik ten Hag as the latest coach to help revive its fortunes after a near decade-long slump toward mediocrity. The decline has led to United’s falling away from contention for the Premier League championship, a title that once had seemed a divine right to fans of one of the world’s most celebrated sporting franchises.

United’s sudden and now protracted run of poor form followed two decades of dominance under the legendary manager Alex Ferguson. Ferguson retired after United’s 20th and last championship in 2013, and a succession of high-profile coaches have been unable to replicate that success as United has fallen further and further behind its bitter rivals Manchester City and Liverpool.

United, owned by the Glazer family, based in the United States, will hope ten Hag will be able to replicate the success he has achieved with the Netherlands’ biggest club, Ajax, which he will continue to lead until moving to England at the end of the season. Under ten Hag, Ajax has regularly punched above its weight against wealthier European rivals, playing a swashbuckling attacking style, with homegrown talent, something that was once a signature of Manchester United teams built by Ferguson.

United said that it had signed ten Hag to a contract through June 2025 and that it had the option to extend the agreement for a further year. United will pay Ajax about $2 million to release ten Hag.

Under ten Hag, Ajax’s talented young squad has won a glut of domestic honors. But his highest profile success came in 2019 when he almost, and improbably, led the team to the final of the Champions League, falling just short after conceding a goal in the final seconds of the semifinal.

“It will be difficult to leave Ajax after these incredible years, and I can assure our fans of my complete commitment and focus on bringing this season to a successful conclusion before I move to Manchester United,” ten Hag said.

The task at United could not be more difficult. As United spent more money than at any other point in its history, its performances have only grown worse, leading to a succession of managerial exits and fan unrest against the Glazers.

Ten Hag will be expected to oversee an overhaul of the club’s poorly balanced and costly roster, but also the culture of the club, where tales of locker room disharmony have frequently found their way into the public domain. News media reports said he would have as much $260 million to spend on new players during the off season.

“It is a great honor to be appointed manager of Manchester United, and I am hugely excited by the challenge ahead,” ten Hag said. “I know the history of this great club and the passion of the fans, and I am absolutely determined to develop a team capable of delivering the success they deserve.”

He will follow the German coach Ralf Rangnick, who was hired on a temporary basis to replace Ole Gunnar Solskjaer, a popular former player with United who was appointed with little high-profile coaching experience and struggled to come to terms with the scale of the task of managing United, a team with a global fan base and expectations of success. He was not the only one to fail to meet those lofty expectations.

United has stumbled from coach to coach with varying formulas — high-profile figures like Louis van Gaal and Jose Mourinho as well as the Scotsman David Moyes, Ferguson’s handpicked successor — without ever looking likely to come close to putting down foundations that could put the team back on course for regular success.

Ten Hag’s appointment comes two days after United was humbled, 4-0, at Liverpool, which is currently engaged in a high octane, neck-and-neck race with City for the Premier League title. United has drifted to sixth place, 23 points behind the leader, City, and is at risk of failing to qualify for next season’s Champions League.

His appointment is not unexpected. United had long targeted him as a possible new coach and had spoken with him on numerous occasions as it looked to plan for the future. United had alighted on ten Hag, 52, along with the Argentine Mauricio Pochettino, the Paris St. Germain coach, who drew admirers for his team-building work at Tottenham Hotspur. In the end it is ten Hag who has been entrusted with the opportunity to revive the fallen giant.

“In our conversations with Erik leading up to this appointment, we were deeply impressed with his long-term vision for returning Manchester United to the level we want to be competing at, and his drive and determination to achieve that,” John Murtough, United’s football director, said.

United’s slide has been so profound that it may be years before ten Hag can be expected to make United challengers for the biggest titles. The current coach, Rangnick, said as much after the miserable performance against Liverpool, during which many United fans left the stadium well before the referee brought an end to the humiliation.

“It is embarrassing, it is disappointing, maybe even humiliating,” a chastened but cleareyed Rangnick said on Tuesday. “We have to accept they are six years ahead of us now. When Jurgen Klopp came they changed at the club and lifted not just the team but the club and city to a new level. That is what needs to happen with us in the next transfer windows.”