I thought it was a tad iffy at the very instant, but with hinsight based on Judah having no objection to it, the stoppage was fine imo. Zab wasn't going to win, though I did think he deserved the chance to finish the fight based on the heart he had shown so far, assuming he could have fought on. Either way the ref should have perhaps let it keep going.. If Zab had taken another flurry on the ropes then sure, stop it.. But like I say, he wasn't about to win, Cotto took anything he had already just fine.