Southampton are sweating on a knee injury suffered by captain Adam Lallana during Saturday's win over Reading.
Saints moved out of the relegation zone with a 1-0 win courtesy of Jason Puncheon but Lallana left on crutches to mar the win.
"We've got him in a brace and he is on crutches at the moment," manager Nigel Adkins said. "That is standard procedure.
"He has got a knee injury and what we will do is assess that over the next 24 to 48 hours and that will give us a better prognosis to how long potentially he will be out for.
"It could be short, it could be longer. We don't know so we won't guess at the moment."
Twice Moore's men led, but twice Portsmouth pegged them back as goals from Gabor Gyepes and Jake Jervis cancelled out efforts from Ash Taylor and Michael O'Halloran respectively.
And despite staying top of the pile on goal difference, Moore was not impressed as his side made it four league games without a win.
"I'm definitely frustrated, only one team was going to win it I thought," he said.
"To get caught defensively like that, its poor defending and we know it. I can't fault the effort that they've given, but they were really poor defensively.
"We're throwing points away. We have two tough away games to come. It just feels like a defeat really.
"Defensively I'm not going to single the person out, he knows what he's done wrong. One man slept and he's cost everyone. It's criminal.
"You need the second goal, but we gave them a lifeline just after half time. We've huffed and puffed but once you get to 2-1, you've got to see the five minute period out. But we gifted them the equaliser. We didn't even get chance to enjoy our goal.
"They get paid to score goals and the others get paid to defend. We don't look like keeping a clean sheet, that's the worry for me."
Matt Ritchie gave the hosts the lead in the eighth minute only for midfielder Danny Hollands' to put through his own net two minutes later.
Di Canio, who had 11 senior players on the sidelines, said: "I am disappointed because we deserved the three points.
"We have to keep the ball and we practice this. We we practice more than other teams in the league, but there is a limit to improve the individual.
"We have to be happy with the way we wear the shirt because we need pride and dignity, and we will win a few games.
"I didn't check the table but before there were five points between us and 12th place, now maybe two, so if we dominate but don't win we will drop.
"Nobody can be angry, my fans or myself, because if you play like this and dominate we will score if we don't concede an own-goal, and 90 per cent of the time we win the game."
