Banned recruit Jake Carlisle could give St Kilda more service when the team is in its premiership window as a result of his season-long suspension, coach Alan Richardson says.

Carlisle signed a four-year deal with the Saints last October but will not be able to join his teammates until September, two months before his doping ban expires.

His lucrative contract included a trigger for a fifth season and Richardson says the Saints can now expect more service from the 24-year-old at the tail end of his career.

Richardson expects Carlisle to eventually form an imposing backline unit with Hugh Goddard, Dylan Roberton and Jimmy Webster when those players are at the peak of their powers.

"Given the journey we are on, we've now got this bloke for one year longer on the back-end … it could actually turn out to be a bit of a positive," Richardson told AFL.com.au.  

"If we were top four last year and this bloke was going to make the difference, then I reckon that's a bit tougher.

"But we need him to be really strong and influential when we are really strong and influential.

"Of course he's part of the journey, but he's going to be part of the Goddard-Carlisle-Roberton-Webster defence … long-term it doesn't change much for us."

While Richardson was positive about the long-term implications of Carlisle's ban, he was disappointed the club would not be able to induct him properly this season.

He said the players had made a big effort to make the former Bomber feel welcome despite being at arm's length from their new teammate.

"I reckon to a man our whole playing group would have touched base," the coach said.  

"Just to say, 'Chin up, tough time, but you're a Saints player and we're behind you'. All that kind of stuff … he found that pretty powerful.

"He's a grown man now who's been involved in six or seven pre-seasons, so he knows what he's got to do to get himself in reasonable nick for when he joins the group again."

While the Saints explore the possibility of replacing Carlisle with a top-up player, Richardson said he was thrilled to have close to a full list in pre-season training.

Forward Tim Membrey and ruckman Billy Longer are being protected in drills, while midfield recruit Nathan Freeman is a week away from joining full training after a hamstring injury.

Otherwise, the Saints have no injury concerns as they ramp up planning for the NAB Challenge.

First-year midfielder Jade Gresham, who was taken with pick No.10 in the 2015 NAB AFL Draft, appears the most likely draftee to figure in the pre-season competition at this stage.

"What we've seen so far is someone who, in and around the stoppage, is more than holding his own," Richardson said of the speedster.

"He might play some early footy, he might not. But we would hope as we improve as a team the evolution sees that it's pretty hard for these blokes to get in.

"With all our young players, if they're ready and they’ve earned the position by the way they've behaved and performed, that'll dictate whether they play or not."