Ralph Hasenhuttl has promised Southampton will sign new players in the January window as they continue to battle Premier League relegation.
The Saints find themselves inside the drop zone in 18th place - with 15 points after 17 matches - ahead of Saturday's crucial trip to Aston Villa, who are one spot above them with a superior goal difference.
Sky Sports News understands Southampton are considering a renewed effort to sign Genk right-back Joakim Maehle in January, while RB Salzburg centre-back Marin Pongracic is another target.
When asked how important the January window is to his side, Hasenhuttl replied: "Absolutely important. We must see that we get some new players in. We know this. The summer window was not perfect for us.
"It is absolutely clear that we must do something with the full-back positions. This is definitely a position we're looking at for the moment and we will do something.
"We have enough quality to score, we score nearly always, but the defence is definitely something we must improve and do something in the transfer market."
The 52-year-old Austrian was also quizzed about his relationship with the Saints' hierarchy, which he insists is strong despite the club's dip in fortunes.
"[The relationship] has not changed from the first day I was here," Hasenhuttl said. "This relationship is important for working together, for developing the club and going through all the periods you go through.
"Sometimes more successful, sometimes more difficult. We are a special club here and we have had that relationship from the first day."
Southampton will be without winger Moussa Djenepo for the trip to Villa Park, while Sofiane Boufal could also miss out through injury.
"Moussa has problems with his hamstring and the risk is too big," Hasenhuttl added. "He didn't train this week. Maybe next week he'll start again but only if there's a reduced risk.
"Boufal is still not in team training. He has still some issues with some movements. So still not able to train with us, but it's getting better and better and I think there's a light at the end of the tunnel.
"We have to wait for him. Maybe he'll be in the squad at the weekend. Maybe he can train tomorrow (Friday). We will try it again and have a look."