West Ham United's co-owner David Sullivan admits the decision to appoint David Moyes as manager is "a gamble".

The Scot replaced Slaven Bilic, who was sacked on Monday (6 November) after months of speculation and a run of just two wins from their opening 11 matches that left the Hammers in the Premier League relegation zone.

The former Everton manager had been looking for a route back into football since he resigned at the end of last season, after his Sunderland side finished bottom of the table with just 24 points.

However, Sullivan is confident the Scotsman, who has signed a six-month deal at the London Stadium, has all it takes to keep West Ham in the top flight.

"This is a gamble but let's see where we are at the end of the season," he told the Sun. "I believe he will keep us up. I have promised him nobody else has been lined up, that we have not signed another manager for next season."

Relegation with Sunderland, the first of Moyes' managerial career, and being sacked by Real Sociedad after just 12 months in charge did little to boost the Scotsman's profile, which has never fully recovered since he endured a nightmare nine-month spell at Manchester United .

Moyes was a surprise choice to replace Sir Alex Ferguson at the helm, when the latter retired at the end of the 2012-13 season but, despite being given a six-year deal, he was sacked before the end of the season as United failed to qualify for a European competition for the first time since 1990.

However, during an 11-year stint at Goodison Park, Moyes established Everton as a top eight side despite a very modest budget.

"This is his job and he has to grab it. It is a big chance for him," Sullivan added. "You don't do what he did at Everton for ten years and become a bad manager — he is a good manager. He did not make this about money. It is about re-establishing himself, taking his chance and keeping West Ham in the Premier League."

While West Ham find themselves in troubled waters, Moyes insisted he was excited by the opportunity of returning to the Premier League and relished the challenge of steering the Hammers to safety.

"I'm thrilled to be back in the game," he told talkSPORT. "It is a massive club, West Ham. It is a well-established club, a well-run football club, so I am looking forward to getting my teeth into it and obviously the job is to make sure we get wins and get ourselves up the league."

The Scotsman's appointment was met with a mixture of disappointment and resignation by West Ham fans, with most of them struggling to believe the 54-year-old is the right man to reinvigorate the club.

However, Moyes remains adamant he can prove his worth in east London and urged the fans to get behind the team.

"Hopefully, I will show everybody what I am really like. I have probably got one of the best win records in the Premier League," he said. "Support the players, support the staff. We are all here to do the job and get West Ham in the correct position and move up the table."