Dan Henderson and Vitor Belfort are not strangers, having met in the cage previously at PRIDE 32. Henderson won that fight by decision and afterward, Belfort popped a positive test for 4-Hydroxytestosterone.
Recently, Belfort told Brazilian MMA site Tatame that he took the fight with Anthony Johnson at UFC 142 after several other fighters, including Henderson, turned it down. Henderson wasn't exactly kind when shooting down that story to Tatame:
"That's not true, this fight was never offered to me," Dan said through an interpreter, his BJJ coach Ricardo Feliciano. "Steroids might be killing Vitor's neurons, he's getting crazy to say something like that".
Henderson is on testosterone replacement therapy, leading some to criticize his taking a shot at Vitor's prior results. Of course, Henderson's situation is doctor prescribed and he has suggested in the past that any fighter who is on TRT be monitored throughout the year to ensure that they are not going above normal levels, so it's hard to treat that as a similar situation.