Keane was left unimpressed by Dalot's defensive work as Morgan Rogers struck twice for Villa in their 2-1 win.
"You can have all the talent in the world, but we mention it time and time again, you've got to roll your sleeves up," Keane said on Sky Sports at the final whistle.
"When the game gets a bit tired, or those moments, you go, 'I'm going to do my bit for the team.' There's too many players, like Dalot, who just don't do enough."
Keane also said: "I won't use the word 'cheating' but they're not doing enough. And after the game, I'd be looking at him, I wouldn't be looking at the other bits, I'd be asking him, 'are you going to stop him?'
"Same with the first goal, when Rogers gets the ball wide, we're all sitting there, we know there's danger. Do they not know there's danger?"