Jimenez fractured his skull last November when Wolves were playing Arsenal and he clashed heads with David Luiz as they both challenged for a header in the box.
The Mexican has been sorely missed at Molineux, especially in the final third because since he joined Wolves the striker has scored 47 goals in the Premier League.
Speaking on why Jimenez must not rush his comeback and why he is unsure what the Mexican will be like when he does return to first-team action, Bull told FFC:
“I wouldn’t rush it because you don’t know if he will come back the same player as before his injury. We don’t know if he will be scared to challenge for a header so I think he’s got to be patient.
“If he can get the odd 20-30 minutes at the end of the season to get his confidence boosted, that will do for me, but just don’t throw him in at the deep end because there’s no need to.”
Wolves have suffered several injuries this season, none more so than Jimenez however, with their joint top scorers, Pedro Neto and Ruben Neves, managing just five in the Premier League.