The Saints will take on the Blues away from home at Stamford Bridge in the Premier League on Saturday evening.
It will be tough for Southampton to win despite Chelsea’s stuttering form, but manager Koeman has made it clear on Twitter that he wants his players to pick up all three points.
Southampton will head into the match at Stamford Bridge on the back of a 3-1 victory over Swansea City at St. Mary’s Stadium.
Prior to that win, the Saints defeated Milton Keynes Dons 6-0 away from home in the third round of the League Cup.
Koeman’s side are 10th in the Premier League table at the moment with nine points from seven matches, while Chelsea are a point behind in 14th.