At what point would champion Hagler have possibly lost to James Toney? By Mugabi I personally think Toney could perhaps get a decision over Marvelous. Just my opinion.
After Mugabi fight seems about right although I think Toney at his best could push any version of Hagler all the way. I think overall had Hagler retired at the right time I don't think he beats the likes of Nunn, Kalambay, after 87.
No I don't see him beating Nunn after the SRL Fight either. Toney could give Marvin a serious test anytime in his reign, especially if Hagler came in underestimate him.
It also depends what type of mindset Hagler comes into the fight with. If Hagler tries to box with Toney like he did Duran then even a prime Hagler could lose a fight to Toney. But if hes firing on all cylinders like he was vs Sibson then I don't see Hagler losing.
I love Hagler but feel the guys that came after in Toney, Jones and Nunn may have all given him hell ... Toney's speed , defense and chin goes the distance against an prime Hagler to a close decision ... Jones simply decisions him like a larger, prime Leonard as the speed and power too much possibly for any middleweight ... Nun at 6' 2" with the southpaw style would be very tough too.. I think all give him serious challenges at his best and all three beat him post Hearns ...
Probably by the end of his career when Hagler started to visibly decline. I think the Tony that beat McCallum would give even prime Hagler a tough fight.
The Sibson fight Hagler was a beast. More than likely at his best. For that Hagler, Toney would have to fight for dear life!
As much as the question is asking for a version of Hagler, I'd say the answer depends as much on which Middleweight version of Toney we're talking about here. Toney turned in variable performances during his time in the division, albeit that, at his best (which is likely McCallum I), he would have been a serious handful for anyone. Re the Question, post-Mugabi is the safe bet. But, even then, I am not entirely convinced that Hagler could not have put something together to match Toney. Maybe I don't bet on that one. Pre-Mugabi, I would probably bet on any version of Hagler to get the win against any version of Middleweight Toney.
Honestly, I see it the opposite way. Toney excelled when fighters were aggressive with him and was at his best counterpunching guys that were on the attack. It was when guys boxed him from the outside he would struggle. One underated part of Hagler's game was his overall boxing ability. When we think of Hagler, it's usually the aggressive banger and that's because of his biggest fights like the Hearns fight which aggression was the appropriate game plan. Against Toney, I don't believe aggression would serve him best. Toney was next to impossible to hurt/stop.
I think Toney's extra speed and defence would trouble Hagler if he tried the boxing route like he did vs Duran, i think putting pressure on Toney is the right way to go about it for Hagler. But educated pressure like McCallum did and often Hagler did aswell, the Hearns fight where Hagler fought like a whirling dervish was a one off as you said. Hagler is a straighter puncher than McCallum and a sharper puncher overall aswell, i think Hagler putting effective aggression on Toney would get him the win in a close decision.
The in shape (albeit a rarity) Toney from the first McCallum fight would decision the Hagler who looked he was punching through custard of the Leonard fight. Prime for prime still this is a very tough match up for Hagler and I would not be surprised if Toney pulled it off, however I’d be siding with the consistent champion in this case.
It's interesting you pick the version of the second McCallum fight. I only note this because I think even a fading Hagler might still be able to outwork Toney and Toney's output was a little less pronounced in the second fight with McCallum than in their first (if my memory serves me correctly). Both performances were top-end from Toney, though. Indeed, the Toney/McCallum bouts themselves were really high quality, in my opinion.