Crystal Palace manager Alan Pardew will be looking for defensive reinforcements in the January transfer window and could also bring in another striker as cover for the injured Connor Wickham.
Wickham is out for the season after undergoing surgery to repair his cruciate knee ligament and Palace, who are 14th in the Premier League table and three points above the relegation zone.
"We need to do something in this window, a lot of teams will move," Pardew told a news conference on Friday. "It's so tight from eighth down. We need to stay with the pack.
"If you stand still you'll go backwards. A left-footed defender would be important this window, but it's not easy to get one.
"The Connor Wickham injury may force us to act in that department too, but it's not easy. We're hunting in a big market and hopefully we'll get the one that fits for us."
Palace snapped a six-game losing run in the league by beating Southampton 3-0 last weekend ahead of Saturday's game against second-bottom Hull City.
"Wins are gold dust in this division. Our game at Hull could define the first half of our season, we've got two very difficult fixtures after (against Manchester United and Chelsea)," Pardew added.
"If our players put in the kind of performance they did against Southampton, then Hull will find it very difficult to beat us."
(Reporting by Simon Jennings in Bengaluru, editing by Ed Osmond)