A rare series of storms had cooled the summer air to an almost tolerable level, though it was steamy as ever inside Floyd Mayweather's gym just a few miles off the Vegas Strip.

With a couple of sparring partners in front of him on a recent Monday afternoon, Mayweather turned up the heat even more.

"Right there, right there!" he yelled at the first hapless pugilist to feel his wrath. "You can't get away. I'll hit you when I want to."