Ex-Blues striker Smith scored twice at the New York stadium as Danny Cowley’s side suffered a damming 4-1 defeat on the road.
And the 29-year-old made sure the following Fratton faithful knew what they were missing when he opened the scoring yesterday.
After heading home in front of the away end, Smith immediately approached the Blues fans and cupped his ears before gesturing to his name on the back of his shirt.
This came after the Pompey fans had, wittily, directed chants at the striker throughout the afternoon due to his underwhelming spell at the club.
Smith scored 10 goals in 37 games across two spells for Pompey, before finding his goal scoring touch with the Millers. The striker scored 10 Championship goals in 44 appearances last term, but already has seven this campaign.
And Holloway believes Smith was within his rights to signal to the travelling support after scoring yesterday.
Speaking on EFL on Quest, Holloway said: ‘‘I’ve always had the belief that you should not give one of your ex-players stick, but the Pompey fans gave him some horrible stick during the game.
‘It’s almost like hitting a crocodile because you don’t want to wake him up, but they certainly did that.
‘Michael Smith has been absolutely fantastic and he deserves to be smug at full-time.’