The Belgium striker has now scored 22 goals this season and 18 in the Barclays Premier League after his hat-trick against Sunderland on Monday night, eclipsing the 17 Dwight Yorke scored on two occasions.
"Christian is a natural monster," said midfielder Delph. "He doesn't do any upper body work whatsoever. He works on his core strength and his legs but that is it."
He added: "When he first came I asked him whether he ate raw meat. John Carew was very similar but Christian is 22.
"Some defenders try to rough him up but everyone who has tried it has failed."
Monday night's contribution was classic in the sense of his opener being a poacher's effort, nodding home the rebound after Simon Mignolet had failed to hold Gabriel Agbonlahor's stinging shot.
Then he climbed high to power home a far post header before beating Mignolet at his near post with a low strike after surging into the box.
"When I saw him jump for the second goal I thought 'he has wings'," said Delph.
"I wasn't sure if he had actually headed the crossbar. If he did I feel sorry for the crossbar. The number of goals he has scored doesn't surprise me.
"We have three games to go and I could put a bet on him to score at least another three or four. He has dragged us through so many games. I was quite surprised he didn't get young player of the season. Obviously he is my pal and I am a bit biased towards him. But even from the outside, you would have thought he would be up there."
Source: PA
Source: PA