Shane Watson was Australia's unlikely bowling star as Pakistan collapsed to 148 on the second day of the first Test at Lord's here on Wednesday. Medium-pacer Watson's return of 5 wickets for 40 runs in seven eventful overs helped leave Pakistan 105 runs behind Australia's first innings 253. Australia's batsmen had struggled in overcast, swing bowler friendly conditions on Tuesday. But, with the skies above Lord's remaining grey, Watson took two wickets for no runs in four balls after being brought on by captain Ricky Ponting.