Why involve the boxer in the plan'!?

I don't get...why at all involve the heavy weight champion in the assassination plan...I know the movie tells up, that's "to get everybody up on their feet to get a clear shot"....but that excuse just looks weak...there would have been plenty of exciting moments in the fight to take advantage of, to take the kill shot without having to over complicate the plan by involving a celebrity..

And why kill the redhead (blonde) girl and the other partner in the crime...Kevin (Sinise) was just as deep in it as his two associates (that he killed)....He said so himself, Rick could be bought off later on if needed...there was little reason to kill them if the cover-up succeeded..if not, he would have been incriminated eitherway..

Also to add, it made Kevin look like a selfish evil jerk, who's only in it for the money, save his own skin and not to secure the defense system to save the lives of his fellow servicemen (that story he told Rick about the sunken submarine and drowning soldiers was likely bogus too in this case).

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wat are you lookin' at punk...