Sadly the Umpire appears to have made an incorrect decision ! If it is true iduring the WC final controversial incident that the batsmen had not crossed on the final 'run' at the instant the fielder threw the ball - It seems they had not done so, therefore only one run plus the boundary from the deflected overthrow should have been awarded.
From
https://www.lords.org/mcc/laws/boundaries
19.8 Overthrow or wilful act of fielder
If the boundary results from an overthrow or from the wilful act of a fielder, the runs scored shall be
any runs for penalties awarded to either side
and the allowance for the boundary
and the runs completed by the batsmen, together with the run in progress if they had
already crossed at the instant of the throw or act.
Law 18.12.2 (Batsman returning to wicket he/she has left) shall apply as from the instant of the throw or act.
I think the reference to law 18.12.2 is important (maybe not in the WC incident).
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"
...If the boundary results from an overthrow or from the wilful act of a fielder, the runs scored shall be..."
The only 'wilful' act relates to the fielder. No mention of the batsman 'wilfuly' deflecting the thrown ball - in the WC incident the batsman was clearly not watching the ball, the deflection was accidental.
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Just one 'wilful' example :- Recognised batsman on strike, number nine (not a recognised batsman) is at non strike end, final ball of over to recognised batsman he steers ball toward boundary fielder, the batsmen set off at very relaxed pace for the single which would place recognised batsman on strike for the coming over, but, before batsmen cross, the boundary fielder carries out a 'wilful' act, he kicks the ball into the nearby boundary marker - thus the four runs for the boundary would be credited, but the single would not count and the batsmen would have to return to their respective wicket or end which they had left - thus placing the number 9 batsman on strike for the new over.
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