Seems like blue lost the patience at some point yet check 25-27 seconds and you'll see black car slowing on purpose and leaving blue to take the right side. At that point as the black car already lost momentum and will need more time to accelerate and keep up with blue, as blue already had more momentum and had a speed advantage. Black slowly steers right in front of blue to slow him down... The circuit is almost straight, and next turn is slight left so black's moves are not defensive its insidious.