But he didn't run into him - if anything, it's Krishna's foot kicking back that initiates the contact. But that's beside the point - there is nothing in the actions of the defending player that can be characterised as a foul under the LotG.
El Grap,
the LotG state
"A direct free kick is awarded to the opposing team if a player commits any
of the following seven offences in a manner considered by the referee to be
careless, reckless or using excessive force:
...
the ref gave a peno, which implies the referee sees the contact as a) a trip and b) carelesss
it's over.
LotG are simple - the defender has an obligation to take care not to trip, because tripping IS a foul. Krishna is entitled to the line he runs and for the normal kick back of his foot to be untouched. The CB is trying to get goal side and cuts behind him, and gets it too tight. Krishna is tripped. Hard luck. Peno.
I simply don't get these arguments it was not a peno. Unless you can show contact was not made, it's a peno. But O'Leary was in good position, WSW made no complaint. All Krishna's biomechanics suggest it was a trip imvho. Pretty straightforward as I see it.
I think it was soft. If I was the coach I'd be looking for my defender to avoid contact in that situation. But he was careless enough to fail to do that. It's a penalty every single time for mine, as defined by the LotG.
Please read the instructions on the application of the LotG, it's in the same document - you're all giving careless a meaning that is not encapsulated by the instructions on how to apply the actual rule.