If you ever put your gun down in a standoff...
...make sure you don't get too far away.
Its's ridiculous that members of his old unit would be so proficient with firearms (far too much so for any police officer. No one short of a navy SEAL would use tactics like this enough to warrant or maintain such a level of skill...and they wouldn't wear suits, saunter around in large posse-style groups, or coincidentally happen to look like average, mid-50s, pear-shaped, NYC police officers), preposterous that six of them would decide to take down the largest criminal stronghold in the city on a whim, and just plain silly that they'd put their guns on the ground when asked and simply let Statham, who they know to be faster and better than all of them, casually walk back over to where his gun is sitting at waist height. Apparently, "firearm awareness" was a common problem in that old unit, Statham's equal-but-opposite former partner (who suddenly pops up in the last third of the movie) goes down for the same reason. I know, "it's a movie", but this was too over the top.