The only big puncher that actually hit Canelo back with hard shots and often was GGG. The other guys were hard punchers too but they failed to let their power shots go, worried theyd get countered by Canelo. I.e smith and Kovalev.
Well, Canelo has answered this question already. First we have to go back to the period between Golovkin I and II. In a casual interview, Canelo rated Golovkin's power as 9/10. This was strange because he claimed not to be bothered by it in the post fight. So already we see Canelo playing little games there. In the recent pressers he has claimed that Kirkland is the hardest puncher he's faced. So that must mean Kirkland has 10/10 power, as opposed to Golovin's 9/10. Now it's all very well and good to be keyboard warriors who've never fought elite level opposition and then claim WE know the hardest puncher Canelo has faced. But are we the ones eating these shots? Are we the brave warriors risking our lives? Absolutely not. So get over your little fanboy fantasies and understand that James Kirkland is the hardest puncher Canelo ever faced.
Kovalev is IMO the hardest puncher that Canelo has faced, but there were so many asterisks against that bout (post-prime, short-camp, vodka-soaked etc etc). Kova himself said that he had "no energy" in that fight I think GGG & Bivol are probably the hardest shots Canelo has had to deal with - and he himself said they were about the same.