London - New West Ham boss David Moyes warned his under-performing players to "step it up" or face the axe as he appeared before the press for the first time on Wednesday.
The former Everton and Manchester United boss replaced Slaven Bilic on Tuesday and faces a tough task to turn around the fortunes of the London club, mired in the Premier League relegation zone.
Moyes has already overseen two gruelling training sessions since he was appointed.
Questions were raised about the fitness levels of the squad under Bilic, with damning statistics showing they were bottom of the class when it came to sprints and distance covered.
But Moyes, who is in talks to bring in no-nonsense former Hammers defender Stuart Pearce as part of his coaching staff, said there would be no easing up on his watch.
"If you are asking me where my best attribute is, it's out on the grass training with players, but we need the players to show it," he said.
"Once they know they are running the least and sprinting the least they need to take responsibility.
"The sessions will be tough for them but hopefully they will enjoy it too. We are working them hard and trying to get the best we can out of them."
Moyes, who believes he needs to rebuild his reputation after a number of managerial failures, said the players were anxious to showcase their worth but said if they did not put the effort in, they would not play.
"Step it up or you won't play, if you don't run you won't play. I'm in a hurry and they need to be in a hurry too," he said.
Moyes has been given a contract until the end of the season, with a clear brief to pull the club away from relegation trouble.
"It's good for us both," said the 54-year-old Scot. "It's good for me because I'm back in, it's what I do and want to do well. I think it's good for West Ham as well, they've got a good manager.
"Managers aren't now having long-term contracts so I'm more than comfortable. If I'd taken over at the start of season I'd have said a year at the time.
"It gives me a chance to see the east end of London, to see the players, and let West Ham see what David Moyes can do.
"My ambition at the moment is only short term, I have to win games, get us away from the wrong end of the table -- and the squad is good enough."
Moyes managed Everton for 11 years from 2002 before leaving the club to replace Alex Ferguson at Manchester United but was dismissed after just 10 months in charge. He also had a disappointing stint in Spain with Real Sociedad.
"I do have a point to prove," he said. "Sometimes you have to repair things and maybe I've got a little bit to repair."
Moyes has been out of management since he resigned from his post at Sunderland at the end of last season after failing to prevent the northeast club being relegated from the Premier League.