Danny Cowley insists that his Pompey squad still has plenty of room for improvement.
A run of three successive victories has sent them to the League One summit at this early stage of the season.
There is now the challenge of back-to-back away games, with a trip to Wigan following Saturday’s match at Doncaster.
And Cowley has to work out which of his players are ready to feature following a punishing couple of weeks.
The Blues boss said: “We’re pleased to still be winning while we’re developing and improving because we’ve still got an awfully long way to go.
“It’s been a good start and if you wanted me to give a mark out of 10 like a school report, I would say a solid seven. We’re a work in progress.
“The opening to the season has been tough for everyone, with five games in the opening 14 days to negotiate.
“It was great to have back-to-back matches at Fratton Park and to finally have our supporters with us again.
"It’s been a good start and if you wanted me to give a mark out of 10 like a school report, I would say a solid seven. We’re a work in progress."
“But now there are two really difficult fixtures on the road at Doncaster and Wigan, and we’ve tried to recover well to ensure there’s freshness in the group.
“We may need to make some personnel changes and we’ll look at where the group are physically before making a call on that.”
Former Pompey midfielder Ben Close could feature against his old club at the Keepmoat Stadium this weekend.
Cowley said: “Ben’s a player that we admire hugely, with a huge amount of skill and a lovely passer of the ball.
“He carries a goal threat as well and if you look at the Doncaster team as a whole, they’ve got a lot of technical players.
“They perhaps had to be more pragmatic at Accrington on Tuesday night and change their style a little bit.
“But being back at home, I expect them to go back to the way the guys they’ve recruited are used to playing.
“We anticipate a really tough game – the fact that nobody won by more than one goal in midweek shows you how tight this league is.”