Despite losing a host of key players as well as former boss Mauricio Pochettino before the beginning of the season, Southampton have made a flying start to life under Koeman.
With the former Feyenoord coach at the helm, Southampton have lost just twice in the Premier League and sit second behind Chelsea.
Koeman feels European commitments for potential top-four rivals such as Liverpool, Tottenham, Everton and Arsenal could help Southampton gain a Champions League berth.
"If you don't play European football that means you have more time during the week for training sessions," he is quoted as telling the Daily Echo.
"And, of course, if you have a lot of changes in the team and a lot of new players you like to try and show how you like to play.
"Maybe [there is an opportunity this season] because they have a tough programme with the Champions League [and Europa League] but one quality that they have is 24 or 26 international good players and we don't have 26.
"That's maybe the one difference between the big ones and Southampton."
