Premier League Preview: Crystal Palace v Southampton
The south-coast club ended a run of five straight defeats in all competitions with a 3-0 win over Everton last Saturday, arresting a slide that had seen them drop out of the top four.
Koeman secured the services of winger Eljero Elia on loan from Werder Bremen earlier in the week as Southampton aim to build on a strong first half of the season in the new year.
Southampton will look to gain momentum with victory at Selhurst Park against a Palace side that is only outside the relegation zone on goal difference and without a win in five matches.
However, Koeman is not underestimating Neil Warnock's hosts.
"I saw a little bit of the Manchester City game [which Palace lost 3-0] and they defended well," Koeman told Southampton's official website.
"City showed their qualities but it is difficult to beat them.
"They are physically strong. In set pieces, maybe they are the strongest team in the league. We have to be well concentrated to have a good result.
"The stadium will be full and we would like to continue with our performance form the Everton win. The confidence is back to normal."
Koeman's men will have to combat Palace's set-pieces without defender Jose Fonte, who is serving a one-match ban.
Jack Cork (ankle) is still on the sidelines along with Jay Rodriguez, Sam Gallagher and Jake Hesketh (all knee).
Meanwhile Palace, whose last win came in a 3-1 triumph over Liverpool in November, have just one absentee, with Marouane Chamakh out due to a hamstring issue.
Palace boss Warnock has conceded that his side requires reinforcement if they are to remain in the English top flight but has challenged his current crop of players to produce their best form over a vital period of festive fixtures.
"The players need a lift and helping out," Warnock said. "They have dug deep.
"I've told them to hang in there and we have a good chance of improving the squad in the second half of the season.
"Last season it was important time for the club. The lads know they need to be at their best over this busy period."