Well it wasn't an ODI so I don't think the same boundary constraints apply....also I meant what I said, that long boundary was a very serious long boundary even with the ropes.....
I dunno how long it is, but am sure its less than the maximum 90 yards (82.3 metres) from the centre of the pitch that is allowed by the ICC.
The longest square boundary in international cricket was at the old WACA pre-1997 (before ropes were used there). From the pitch on the edge of the square, and using my crappy Google Earth skills on old WACA photos, the longer square boundary from the centre of the pitch to the fence was approx. 98 metres (a 100 metre shot from the crease to the part of the fence where it extends furthest from the batsman), which makes the two sixes Robin Smith hit over that fence during the 1992 World Cup England vs India match phenomenal. The one off the spinner would require a lot of strength and power, even with David Warner's bat. No chance in a million years I could ever do it.
Found an aerial photo of the old WACA in 1995, and you can see it would take one hell of a big hit from a then thinner 1990s-style cricket bat to hit a horizontal shot that distance over the fence at the longer boundary.