The resounding score-line marked Cherries’ heaviest home loss since defeat by the same score to Liverpool in the Premier League in December 2018.
Early headed goals from Michail Antonio and Lucas Paqueta set the tone, before Declan Rose slammed in a third before half-time.
O’Neil tried to change momentum with his substitutions, but Cherries could not pull a goal back, eventually conceding again through an acrobatic Pablo Fornals strike.
Asked how he would sum up the loss,
Gary O’Neil said: “Not good enough in both penalty areas. West Ham have a couple of real strengths and we weren’t able to cope with them, basically. Whatever happened in between becomes irrelevant if you’re not able to deal with one of their key strengths. David (Moyes) said to me afterwards obviously it was a never a 4-0 game. We obviously dominated the ball. But West Ham have real strengths in that they attack set plays well, they’re physical, they’re good in the air and they can counter-attack. If you don’t match their physicality in our penalty area for the first goal and even for the second goal, 12 minutes in, 2-0 down, you’ve not been able to cope with one of their key strengths and then you’ve set the game up perfectly for them to sit in as they wanted to and try and catch you on the counter. And then on the flip side of that, we arrive in the final third, create a lot of chances and aren’t good enough to stick any away at the moment. If you want to look at the real reason West Ham beat us today, it’s because their strengths, we couldn’t cope with.”
Cherries slip to 15th with this defeat, five points clear of the relegation zone with six games to play.