The former Spurs boss believes the Gunners made a mistake by choosing the Brazilian over the English veteran
Arsenal made a mistake in signing David Luiz and should have opted to snare 'obvious choice' Gary Cahill, according to Tim Sherwood.
The Gunners desperately needed defensive reinforcements and chose to ignore Chelsea veteran Cahill as an option - who was available early in the summer before signing with Crystal Palace on a free transfer.
Instead, Arsenal picked up another Blues centre-half - David Luiz - in a surprising £8 million ($10m) deal on deadline day.