Sylvain Distin is the latest Portsmouth player to urge the club to sign more new players during the transfer window.
Pompey were without six first-choice stars for last weekend's defeat at Sunderland which dropped them down to ninth in the Premier League table, with Glen Johnson and Sean Davis out through injury and Sulley Muntari, Kanu, John Utaka and Papa Bouba Diop away on African Cup of Nations duty.
Harry Redknapp is working hard on bringing in some new faces before the close of the transfer window and Distin fears they could lose their way in the battle for a Uefa Cup place if they do not act in the transfer window.
"I think we need to invest in players," insisted Distin.
"Clubs around us are going to do it. If we want to finish in the top six or seven we are going to have to do it too.
"We do not have enough players. We need to get some in. If we have injuries or suspensions we are in trouble.
"There were players playing at Sunderland who had not played one game this season.
"It has been a good season and we have got some good players, but to be honest I was already expecting some to be here by now.
"The more we are going to wait, the more difficult it is going to be to get some players, and harder for us to have a reaction.
"If you want to push for Europe you have to invest in every transfer window.
"Time will tell if we lose what we have achieved this season. We have to sort it out otherwise we are starting to drop off."