The midfielder capped another fine performance by netting the all important second goal against one of the Black Cats main contenders in the race for promotion.
"I'm delighted for Jeff," said the Sunderland boss.
"We were all disappointed on Wednesday night when he was sent off but he showed his commitment and earned his goal.
McCarthy Praise For Whitley
"That was a good three points but it wasn't pretty between two top teams desperate for points. Goals change games and we got them and I think we deserved our victory.
"West Ham are in a play-off spot so it was important that we won after Preston. It was nice to beat a team above us and I thought the game was there for us to win.
"I didn't want us to change the game and it didn't happen. We have battered teams off the park without reward and while we haven't dictated West Ham, we have nicked two goals."