"At 3-0 we tried to do something, but they then made it 4-0 and it wasn't easy," added Grant.
The Hammers now face two cup games, an FA Cup tie against Barnsley on Saturday followed by a Carling Cup semi-final first leg match at home to Birmingham three days later.
Grant said he would have enjoyed the prospect of those matches had his side not been depleted by injuries, with Kieron Dyer, Herita Ilunga, Benni McCarthy, Thomas Hitzlsperger, Jack Collison and Manuel da Costa currently missing from the squad.
"We're a little bit short and there is pressure going into the cup games," said the Israeli.
Meanwhile, Newcastle manager Alan Pardew sang the praises of his side's hat-trick hero Leon Best and midfielder Joey Barton, who he believes deserves an international call-up.
Best made his first league start for the Magpies, replacing the injured Shola Ameobi who joined star striker Andy Carroll on the sidelines.
Pardew lauds hat-trick hero Best
"Leon has been banging on my door to play and I knew he would have a chance during this busy period. He kept his focus on wanting to play and there was hunger in his eyes," said Pardew, who was facing a team he managed for three years.
"But he was the beneficiary of our midfield's good play, particularly Barton's.
"His midfield display was good as I've ever seen. And from what I've witnessed of his performances since I've joined the club, I think he deserves an England call-up.
"He's had a temperament problem in the past but I haven't seen that since I've been here."
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