Moyes begins work immediately ahead of the New Year's Day fixture with AFC Bournemouth at London Stadium.
Pellegrini was sacked after last Saturday's 2-1 home defeat by Leicester City, their ninth loss in 13 games after a promising start to the season. I could be a few championship people and people would say that's not a very good thing, but you could have said that with Sheffield United and in fact they were sensational. "The game finished and I got a call after that and it just all kicked into gear from then".
The Scot guided the Hammers to security in his first spell on the membership earlier than they determined to not supply him a brand new contract and as an alternative appointed Pellegrini.
Moyes said: "I think that how well Sheffield United are doing with what probably, with respect, looked like the team which has come up from the Championship, has proved that there might be many players who can step up.
And I'm coming here to West Ham initially to try and get us wins and away from the wrong end of the table", he declared.
15 killed, 66 hurt after passenger plane crashes in Kazakhstan
Picture: Vladimir Tretyakov/AP The Kazakhstan plane with 100 people aboard crashed shortly after takeoff early Friday. According to The Guardian , the plane crashed at Almaty airport in Kazakhstan and was carrying 100 people.
"They're looking at being a club in the top-six, I thought they'd have a chance to be honest, at least top-half of the table with the squad that they've got and they've totally underachieved".
Moyes confirmed that Irvine and ex-England U21s boss Stuart Pearce would form part of his backroom staff as he attempts to save West Ham from the drop.
Moyes was hired by West Ham in November 2017 to replace Slaven Bilic with the east London club in the relegation zone.
'It is fabulous to be again, ' Moyes advised the membership's web site. Bournemouth looked like flawless opponents to kickstart their campaign given Howe's side had lost seven of their previous nine matches before this but that did not take into account the fact they came into this meeting unbeaten in their last six games against West Ham. "We also want something we know gives us a level of consistency most Saturdays".
"The job first and foremost is to make sure we get away from this position", he said. "We didn't talk about the past, we were just talking about the team now, what we have to do and the position we're in".