WATCH: Roy Keane, Ronaldo and five seconds that sum up the Irish force of nature

Respect is a funny thing.

Too little and you are accused of being aloof or uncouth; too much and you are dismissed as a cowering fool. In terms of competitive football, one thing is for sure - if it is offered unconditionally and not reciprocated, you've already lost.

Roy Keane is a hard man to please. He doesn't readily offer respect to anyone, and doesn't much care if you respect him.

He won't give an inch to the opposition and is hardest upon his own number. Any sign of weakness or overly-abundant praise is intolerable. He never sees himself as inferior to anyone, and nor should anyone associated with him.

What you must never do, in Keano's book, is give your rival any sign of encouragement or a sense of superiority prior to an encounter. He disdainfully recalls a former Manchester United teammate doing just that on a Champions League night.

"As we stood for the UEFA anthem before the second leg of the Champions Cup semi-final with Bayer Leverkusen, one of our players was shaking. He was afraid. Played for his country, won championships, big star - afraid of taking the step up."

Such behaviour is not on. The man who famously told an unnerved Patrick Vieira that he'd see him 'out there' knows a thing or two about preemptive psychological blows. Body language, power plays and steely stares set the tone for battle.

This mentally was perfectly apparent prior to United's Champions League quarter-final game with Inter Milan at the San Siro in 1999. The match ended 1-1, resulting in the Manchester club progressing to the semi-finals on away goals.

But this very short and seemingly innocuous footage of both lineups partaking in handshakes before kick-off says so much about who and what Roy Keane is and always will be.

The Internazionale team of the day was star-studded to say the least. Giuseppe Bergomi, Javier Zanetti, Roberto Baggio, Diego Simeone and Brazilian Ronaldo all graced the starting XI. That team, in that foreboding stadium, made for a scary proposition.

As Keane made his way down the Inter lineup and grasped outstretched hands with cursory derision, Simeone and Ronaldo decided that was the perfect moment to readjust their socks with synchronised timing. It was clearly premeditated.

The intention was to make the United skipper wait and establish the upper hand. Keano was having none of it. Whether uncivil or not, he strolled past them as if they were his bowing inferiors. Sans handshake, the pair were left somewhat perplexed.

Some would suggest that the Cork man was lacking in decency to not shake the hands of such internationally renowned superstars. An alternative view is that both the Argentine and Brazilian were playing silly buggers to start with.

It's doesn't really matter, and it didn't really matter to Keane. He was and is acutely aware of his own brilliance, and wasn't going to let anyone take command. Fuck respect when you've got a job to do and dreams to crush.

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