Anton Walkes has called for unity as Pompey try to improve their patchy form.
The Blues have won just twice in 2018 to fall from sixth spot in the League One standings down to 11th.
But they remain only four points adrift of the final play-off spot with 11 matches of the campaign remaining.
And with Gillingham visiting the south coast on Saturday, Walkes is confident that Pompey can rediscover that winning feeling.
He said: “We’re at the business end of the season now and the run we’ve been on has been dreadful.
“But we’re still in it and a few back-to-back wins can see things change quickly, so that’s what we have to focus on.
"We know the fans will be behind us from the first minute to the last and I’m sure that will be the case against Gillingham."
“We’ve just got to keep our heads up and work together as a group. That’s not hard because there’s a great bunch of lads here.
“Everybody pushes each other on and demands more, so it’s just about eradicating a few errors here and there.
“A lot of players are out injured, but that’s when other guys who haven’t been involved as much need to come in and be ready to do a job.
“We know the fans will be behind us from the first minute to the last and I’m sure that will be the case against Gillingham.”
Pompey had a rare Saturday off last week after their scheduled trip to Bradford was postponed because of the snowy conditions.
Walkes said: “It was unexpected to be able to take things a bit easier for a couple of days!
“But we’ve had a lot of games in quick succession in recent weeks and sometimes it’s good to be able to ease off the gas for a bit.”