Trotters striker Davies, 33, shook off concussion to start at Aston Villa were he equalised in the 1-1 draw.
And Bolton defender Knight, 30, said: "He's even a handful in training.
"Defenders don't want to play against him because he's always likely to leave a bit on you.
"People think he is just a good header of the ball but he's much more than that.
"We just hope we can keep him fit for the rest of the season.
"It was a good finish and maybe he could have had one or two more."