rafael nadal was bidding for a ninth barcelona open title this year .
but the world no 4 lost to italian fabio fognini 6-4 , 7-6 -lrb- 8-6 -rrb- in third round .
nadal has won just one title since winning his 10th french open last june .
the spaniard admitted it was a ` very sad day ' following the defeat .