Greg Halford admitted Pompey’s rash of cards is offering cause for concern.
The Blues defender spoke of his worry at Pompey rising number of cautions and dismissals after their 1-0 loss at Hull.
Luke Varney was ordered off at the KC Stadium on Saturday, making it 21 yellows and two red cards for Pompey this term.
Boss Steve Cotterill disputed whether Varney should have been giving his marching orders for a second-half lunge on James Chester.
But Halford knows the threat of suspensions hitting Cotterill’s side means the early-season spate of cards needs to be reined in.
Halford said: ‘On the pitch, the red card looked harsh.
‘We’ve gone into the referee’s changing room (after the game) and questioned him a little bit.
‘He said Luke went in with a straight leg and studs high.
‘The replay clearly shows that’s not the case.
‘It’s not a red card, but of course (the cards are a concern).
‘We can’t afford to get suspensions.
‘The games are going to come thick and fast.
‘It might be a blessing we’ve got the international break coming up.
‘But two sendings off in two games is definitely a worry.
‘Luke will be missing for three games, depending on an appeal.
‘But we get Liam (Lawrence) back, which is a bonus, and hopefully Kits will get fit.’
Halford offered no excuses for the defeat against Hull and the manner of the performance which paved the way for the loss.
He pulled no punches about how his side failed to compete against the Tigers for long periods.
And the 26-year-old felt Pompey got what they deserved for how they played.
Halford said: ‘There weren’t many chances created and there wasn’t a shot on target, so we didn’t deserve anything.
‘We didn’t compete and didn’t fight for second balls. We were lacklustre.
‘I don’t know why that was. I couldn’t say. I have no idea.
‘We knew they would come out strong and we’d have to match them. We didn’t.
‘Second balls have been our problem all season and last season. We don’t compete.
‘It was a bad goal to give away, a catalogue of errors, really.
‘I win the header, we lose the second ball and it drops to (Robert) Koren.
‘We know he’s right-footed but we show him inside on to his right foot and he puts it into the bottom corner.
‘There’s a lot of mistakes there, so we deserved to be punished for it.’