Anderson made 39 appearances last term scoring six goals, and has bagged 27 finishes in 174 outings since joining the Imps in 2017.
Danny Cowley took Anderson to Lincoln after working with the winger at Braintree, and the 24-year-old is believed to be on Pompey’s summer shopping list.
The former Peterborough man is a free agent and Appleton has revealed the reasons he made the call - citing Anderson’s style of play as not being suited to how he wants to operate.
Appleton told Lincolnshire Live: ‘It was difficult. Anyone who knows me and has heard me speak about Harry knows that I hold him in very high regard as a person.
‘He’s a brilliant character and he’s done fantastically well for the football club.
‘But the reality is, for us to move forward we have to, one, keep trying to freshen things up, and, two, try to improve all the time.
‘With the way we play, our wide players are asked to do certain things. To be fair to Harry, he tried his best and he did improve.
‘But the reality is, his strengths as a wide player are very different to what we want from our wide players.
‘It was one of them where Harry’s at an age where he’s used to playing lots of football.
‘He’s a lot younger than what people think because he’s been around so long. I think it’s important he plays week in, week out and I can’t guarantee him that.
‘So I think the best thing for him was to move on and try and get regular first-team football.’
A message from the Editor, Mark Waldron
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