In fact, Grice felt his troops were the ‘better team’ for large periods of what ended up a heavy loss on the road in Dorset.
The US Portsmouth boss was unhappy with the awarding of a third-minute penalty which put the hosts on the way to their emphatic victory, while Grice was again counting the cost of his side's wasteful nature in front of goal.
‘Anyone that was there yesterday - I hate saying it because what's happened has happened - but anyone at the game would know it wasn't a 5-1 game,’ insisted the US Portsmouth boss.
‘There was the penalty (for Shaftesbury) right at the beginning which set the tone for the game. In my opinion, it was an extremely harsh decision (penalty). I'd done my homework with them (Shaftesbury). I know going forward they're very, very good but defensively they're not.
‘There were times, especially in the first half, where we were putting through balls through from our defenders and one pass and we were getting through.
‘We had chances in the second half and we were actually the better team - I don't care who you ask - we were the better team, playing more football and retaining the ball. The big thing is - it's the same thing we've suffered from all season - is putting our chances away.’
Greg Peel's spot-kick opener on three minutes after Cam Quirke had been 'harshly' adjudged to have committed a foul in the eyes of Grice separated the sides at the break.
Asa Phillips' effort eight minutes after the break was followed by Luke Burbridge adding a third just four minutes later to put Shaftesbury in control at 3-0 to the good inside the hour mark.
US Portsmouth had some slight hope when Quirke made up for giving away the first-half penalty by netting on 64 minutes.
But Luke Delaney grabbed the hosts' fourth on 78 minutes before Burbridge rounded off the rout with his second two minutes from the end of normal time.
The Czech Republic youngster, currently studying at the University of Portsmouth, has moved to Southern League Division One South Lymington, making his debut in their 3-1 league defeat at Magnotsfield yesterday.