The Royals have won just one of their opening five matches in all competitions in what has been a slow start to the campaign.
Carter has been underwhelmed with his squad's beginning to the season and now wants to see them raise their level.
Portchester head into their home meeting with second-placed Brockenhurst still winless in their opening two league fixtures.
The Royals boss has no doubt he has the quality within his squad for them to be fighting at the top of the table - it's just a case of them stepping up to the mark. And Carter is eager to see that starting against Brockenhurst on Saturday.
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‘They need a rocket up them and that’s what they’re going to get. We’ve got good players, we’ve got the ability there, but we’re not just going to walk in and win games,’ said Carter.
‘We need that momentum, we’ve got what I would consider a nice little run coming up now, we’re starting to expect us to kick in now.
‘There are no more excuses, the season’s started, we’ve had five games together and we need to start gelling, getting points on the board and start winning games.
‘We’ve had two draws in the league, we need to get our league campaign started now if we’ve got any chance of being up and around it at the end of the season.’
Portchester striker Kieran Roberts is the Wessex Premier's joint leading scorer with six goals in five games.
However, Carter says others within his squad must start stepping up and contributing goals rather than becoming overly reliant on Roberts.
Carter said: ‘We need to stop conceding goals and making mistakes is what we need to cut-out.
‘Kieran Roberts is the leading scorer in the league but we need to be scoring goals from elsewhere.’
Carter has dual-signed Owen Roundell from Gosport while he is awaiting international clearance on the returning Stan Bridgman who is back at the club following a brief spell in Ireland.
Curt Da Costa (heel) is doubtful to be fit in time for Saturday's Brockenhurst meeting and the Hampshire Senior Cup tie with Wessex League new boys Infinity on Monday.
Lee Wort (hamstring) and Conor Bailey (knee) will be assessed at training this evening ahead of the weekend.